V1.11.0: gear that applies itself, equipping that matters, a character panel

- Weapons and items can carry effects: bonuses and penalties to AC, speed,
  initiative, max HP, passive Perception, ability scores, saving throws
  and skills, plus a note. They apply on their own while equipped and stop
  when the thing comes off. Armor is an item with an AC effect. The DM
  sets them with "Effects" on a row in the weapon or item pool.
- The sheet's "armor bonus" is now "Extra AC", the DM's own adjustment on
  top of gear, and only the DM can set it.
- Only what is equipped counts: a weapon has to be equipped to be used in
  an encounter. A character can have two things equipped at once, one of
  them a weapon (campaign settings). Equipping at the limit is refused
  with a message, and can be changed at any time, mid-encounter included.
- A built-in item library: armor, shields, worn gear and supplies, with
  their effects set. The weapon library gains paired weapons (a pair of
  daggers is one weapon).
- A floating character button on every page opens a panel with a
  character's numbers and everything they hold, with equip ticks. Players
  get their own characters, the DM everyone's, and each character card in
  an encounter has an Inventory button. It replaces the quick stats drawer.
- A player's own characters stand out: marked and highlighted in
  encounters, with a button that jumps to their card; highlighted on the
  party screen; and listed once, not twice, on the campaign page.
- All packages at version 1.11.0.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

docs/ITEMS.md

@@ -14,10 +14,12 @@ level up the same way weapons do), [SPELLS.md](SPELLS.md),
 3. [A character's inventory](#3-a-characters-inventory)
 4. [Item levels](#4-item-levels)
 5. [Dice on items](#5-dice-on-items)
+   - [Effects: armor and other gear that changes the sheet](#effects-armor-and-other-gear-that-changes-the-sheet)
 6. [Starting items](#6-starting-items)
 7. [Items as rewards and for sale](#7-items-as-rewards-and-for-sale)
 8. [Permissions](#8-permissions)
 9. [What is not modelled](#9-what-is-not-modelled)
+10. [The complete item library](#10-the-complete-item-library)
 
 ---
 
@@ -27,7 +29,8 @@ level up the same way weapons do), [SPELLS.md](SPELLS.md),
   anything that is not a weapon or a spell.
 - A character's **inventory** is the items it holds from that pool. Players
   cannot type in items of their own.
-- The DM creates items and hands them out. Players can only tick Equipped.
+- The DM creates items and hands them out. Players can only tick Equipped,
+  and only so much can be equipped at once (section 3).
 - Items are **descriptive**. Holding or equipping one never changes a number
   on the sheet.
 
@@ -43,8 +46,16 @@ The pool is the "Items Pool" card on the campaign page (DM only).
 | Starts at level | 1 to 9. The lowest level this item can be (section 4) |
 | Growth | Standard, Powerful or Legendary. Only matters if the item has dice |
 | Starting option | Whether a brand-new character may pick it in the builder (section 6) |
+| Effects | What it does to whoever has it equipped: bonuses and penalties to the sheet's numbers, and a note (section 5) |
 
-- **Adding:** the "+ Add Item" form. There is no built-in library of items.
+- **Adding:** by hand with the "+ Add Item" form, or with "📚 From Library",
+  which offers 32 ready-made items: light, medium and heavy armor, shields,
+  worn gear such as a Ring of Protection, and common supplies. Each is copied
+  into the pool with its effects already set (Chain Mail: +6 AC, −10 Speed,
+  and a note about Stealth), at starting level 1 and not ticked as a starting
+  option. The copy is yours to change. The full list is in section 10.
+- **Effects:** the "Effects" button on an item's row. The row shows what the
+  item does under its name.
 - **Changing:** starting level, growth (when the item has dice) and the
   starting-option tick box can be changed in the table. Name, description and
   dice cannot be changed on screen once created (the API accepts it); remove
@@ -67,8 +78,39 @@ On a character's sheet, the DM picks an item from the pool and clicks Give.
 - Quantity cannot go below 1; to take the last one away the DM uses ✕.
 - **Using up** an item (drinking a potion) is not automatic: the DM lowers the
   quantity or removes it.
-- **Equipped** is a label. It does not change Armor Class or anything else;
-  armor is represented by the single "armor bonus" number on the sheet.
+- **Equipped** is what switches an item's effects on (section 5), and what
+  shows the item on the character's encounter card.
+- **Only what is equipped counts.** A weapon has to be equipped to be used
+  in an encounter, and gear only gives its effects while equipped. What is
+  not equipped stays in the pack: still the character's, still listed on the
+  sheet and in the character panel, but not in hand.
+- **There is a limit on how much can be equipped at once**, set per campaign
+  in Campaign Settings ("Equipped at once"):
+
+  | Setting | Starts at | Means |
+  |---|---|---|
+  | Things equipped at once | 2 | Weapons and items together |
+  | Of which weapons | 1 | So: one weapon, or one weapon and one item, or two items |
+
+  Armor and shields are items and count toward the limit. With the starting
+  numbers a character can have a weapon and a shield, or a weapon and armor,
+  but not all three; a DM who wants armor, shield and weapon together sets
+  the first number to 3.
+- **Putting something on when the limit is reached is refused**, with a
+  message naming what is already equipped. Take something off first.
+- **Equipping can be changed at any time, including in the middle of an
+  encounter**, by the owning player or the DM: on the sheet, or in the
+  character panel (the 🧙 button, or "🎒 Inventory" on the character's
+  encounter card).
+- Lowering the limits takes nothing off anyone. A character with more on
+  than the new limit keeps it until they change what they have equipped.
+- Everything arrives unequipped: gear from the DM, from a reward, bought, or
+  given by another character.
+- The whole pack is always listed: on the sheet, and in the **character
+  panel** (the floating 🧙 button, on every page), which the owning player and
+  the DM can open from anywhere, including from the character's card in an
+  encounter. Things the character is too low level to use are shown and
+  marked "needs level N", not hidden.
 
 **Passing items on.** A character's owner (or the DM) can give some or all of
 a held stack to another character in the campaign from the "Give to Another
@@ -111,6 +153,48 @@ rungs per level depending on Growth. The full ladder is in
 The dice are shown beside the item in the inventory. Nothing is rolled or
 applied automatically; use the dice roller.
 
+### Effects: armor and other gear that changes the sheet
+
+Armor, shields, rings, cloaks and the like are ordinary items that have
+**effects**. An effect is a whole number, positive for a bonus and negative
+for a penalty, on one of the sheet's numbers:
+
+| It can change | Examples |
+|---|---|
+| AC | Chain mail +6, a shield +2, a cursed cloak −1 |
+| Speed | Heavy armor −10, boots of speed +10. Speed never goes below 0 |
+| Initiative | +2 |
+| Max HP | +5. Max HP never goes below 1 |
+| Passive Perception | +5 |
+| An ability score (STR, DEX, CON, INT, WIS, CHA) | Gauntlets +2 STR. The score changes, so its modifier and everything built on it (saves, skills, attacks, HP from CON, AC from DEX) change with it. A score never goes below 1 |
+| All saving throws, or one ability's saves | A ring: +1 to all saves |
+| All skill checks, or one skill | Noisy armor: −2 Stealth |
+
+An item can have up to 12 effects, one per number, each from −100 to +100,
+plus a **note** for what is not a number ("Disadvantage on Stealth",
+"Resistance to fire").
+
+- **They apply on their own.** While a character has the item **equipped**
+  and is high enough level to use it, its effects are part of every number
+  the app shows for that character: the sheet, the character panel, the party
+  overview and their encounter card. Nothing has to be typed in.
+- **Unequipping takes them away again**, as does giving the item away, the DM
+  removing it, or the character dropping below its level.
+- **Effects add up.** Two different items with +1 AC give +2. Carrying two of
+  the same item does not double it: a stack counts once.
+- **The sheet says where each change comes from.** A "From Equipped Gear"
+  card lists every item in force with what it is doing, and its note.
+- **Max HP can move.** If taking something off lowers a character's maximum
+  HP below their current HP, current HP comes down to the new maximum.
+- **Only the DM sets effects**, with the "Effects" button on the item's row in
+  the pool. Changing them changes the sheet of everyone wearing the item,
+  straight away.
+- The DM also has an **Extra AC** number on each sheet, added on top of gear,
+  for anything an item does not cover. It can be negative.
+
+Weapons can carry effects in exactly the same way
+([WEAPONS.md](WEAPONS.md), section 2).
+
 ## 6. Starting items
 
 In the builder's equipment step a new character can pick items that are:
@@ -151,11 +235,94 @@ and [ENCOUNTERS.md](ENCOUNTERS.md), section 10.
 
 ## 9. What is not modelled
 
-- Any effect of an item on stats (AC, speed, abilities)
-- Armor and shields as items
+- Armor rules beyond a flat bonus: armor does not replace 10 + DEX, cap the
+  DEX bonus or need a Strength score (set the AC effect to match)
+- Effects on attack rolls, damage, spell save DC or proficiency bonus
+- Effects that depend on something (only at night, only against undead), or
+  that grow with the item's level
+- Advantage and disadvantage as rules (write them in the note)
 - Using up items automatically, charges, and attunement
 - Weight, carrying capacity and containers
 - A price on the item itself: a price is set each time it is put up for sale
 - Selling items back (record the gold change in the money log)
 - Swaps as a single step (each side gives separately), and asking the
   recipient to accept
+- Hands and body slots: the limit is a plain count, so nothing stops two
+  suits of armor being equipped if the count allows it
+- Swapping automatically: equipping at the limit is refused, not exchanged
+
+## 10. The complete item library
+
+Everything "📚 From Library" offers. "While equipped" is what the item does
+to the sheet of whoever has it on.
+
+Armor is a flat bonus to AC on top of 10 + Dexterity: each suit's bonus is its
+standard AC less 10. What a flat bonus cannot say (heavy armor ignoring
+Dexterity, a Strength requirement, disadvantage on Stealth) is in the note,
+for the DM to apply or to build into the numbers of their own copy.
+
+This list is written from the app's own data by `npm run docs:lists` (in `/backend`). Re-run it after changing the data; do not edit the list by hand.
+
+<!-- BEGIN GENERATED: item-library -->
+### Light Armor (3)
+
+| Item | While equipped | Note | Dice | Description |
+|---|---|---|---|---|
+| Padded Armor | +1 AC | Disadvantage on Stealth checks. | — | Quilted layers of cloth and batting. |
+| Leather Armor | +1 AC | — | — | Boiled leather breastplate and shoulder guards over soft leather. |
+| Studded Leather | +2 AC | — | — | Tough leather set with close rivets and spikes. |
+
+### Medium Armor (5)
+
+| Item | While equipped | Note | Dice | Description |
+|---|---|---|---|---|
+| Hide Armor | +2 AC | Standard rules: counts at most +2 from Dexterity. | — | Thick furs and pelts. |
+| Chain Shirt | +3 AC | Standard rules: counts at most +2 from Dexterity. | — | Interlocking rings worn between layers of clothing. |
+| Scale Mail | +4 AC | Disadvantage on Stealth checks. Standard rules: counts at most +2 from Dexterity. | — | A coat and leggings of leather covered in overlapping metal scales. |
+| Breastplate | +4 AC | Standard rules: counts at most +2 from Dexterity. | — | A fitted metal chest piece worn with supple leather. |
+| Half Plate | +5 AC | Disadvantage on Stealth checks. Standard rules: counts at most +2 from Dexterity. | — | Shaped metal plates covering most of the body. |
+
+### Heavy Armor (4)
+
+| Item | While equipped | Note | Dice | Description |
+|---|---|---|---|---|
+| Ring Mail | +4 AC | Disadvantage on Stealth checks. Standard rules: adds no Dexterity. | — | Leather armor with heavy rings sewn into it. |
+| Chain Mail | +6 AC, −10 Speed | Disadvantage on Stealth checks. Standard rules: adds no Dexterity, and needs Strength 13. | — | Interlocking metal rings over a layer of quilted fabric, with gauntlets. |
+| Splint Armor | +7 AC, −10 Speed | Disadvantage on Stealth checks. Standard rules: adds no Dexterity, and needs Strength 15. | — | Narrow vertical strips of metal riveted to a leather backing. |
+| Plate Armor | +8 AC, −10 Speed | Disadvantage on Stealth checks. Standard rules: adds no Dexterity, and needs Strength 15. | — | Shaped, interlocking metal plates covering the whole body. |
+
+### Shields (2)
+
+| Item | While equipped | Note | Dice | Description |
+|---|---|---|---|---|
+| Shield | +2 AC | — | — | Wood or metal, carried in one hand. |
+| Tower Shield | +3 AC, −5 Speed | — | — | A wall of oak and iron, as tall as its bearer. |
+
+### Worn Gear (10)
+
+| Item | While equipped | Note | Dice | Description |
+|---|---|---|---|---|
+| Ring of Protection | +1 AC, +1 all saves | — | — | A plain band that turns blows aside. |
+| Cloak of Protection | +1 AC, +1 all saves | — | — | A heavy cloak that seems to catch what was meant for you. |
+| Cloak of Elvenkind | +5 Stealth | With the hood up, others have disadvantage on Perception checks to see you. | — | With the hood up, its colour shifts to match what is behind it. |
+| Boots of Striding | +10 Speed | — | — | Light, tireless boots. |
+| Gauntlets of Might | +2 STR | — | — | Iron-banded gauntlets that lend a giant’s grip. |
+| Gloves of Thievery | +5 Sleight of Hand | — | — | Thin grey gloves that all but vanish when worn. |
+| Amulet of Health | +2 CON | — | — | A red stone on a golden chain, warm against the skin. |
+| Headband of Intellect | +2 INT | — | — | A silver circlet set with a pale blue stone. |
+| Sentinel Charm | +2 Initiative, +5 Passive Perception | — | — | A brass eye on a cord that never quite closes. |
+| Stone of Good Luck | +1 all saves, +1 all skill checks | — | — | A polished agate that sits well in a pocket. |
+
+### Supplies (8)
+
+| Item | While equipped | Note | Dice | Description |
+|---|---|---|---|---|
+| Healing Potion | — | — | 2d4+2 | A red liquid that glimmers when shaken. Drink it to regain hit points. |
+| Rope (50 ft) | — | — | — | Hempen rope. Holds a climber. |
+| Torch | — | Held in a hand to give light. | — | Burns for an hour, lighting 20 feet brightly. |
+| Hooded Lantern | — | Held in a hand to give light. | — | Bright light for 30 feet; the hood dims it to a glow. |
+| Rations (1 day) | — | — | — | Dried meat, hard biscuit, nuts. |
+| Bedroll | — | — | — | A blanket roll for sleeping rough. |
+| Thieves’ Tools | — | — | — | A file, picks, a small mirror, narrow scissors and pliers. |
+| Healer’s Kit | — | — | — | Bandages, salves and splints. Steadies a dying creature without a check. |
+<!-- END GENERATED: item-library -->