Phase 3: object tracker

Game-file footprint unchanged: still one line in main.lua.

Three-level navigation as specified in D2: Ctrl+PageUp/Down cycles categories,
PageUp/Down cycles kinds, Shift+PageUp/Down cycles instances of that kind, Home
announces where it is.

- categories.lua: flag-first classification into Creatures, Items, Alchemy,
  Interactables, Exits and Terrain features, reusing the game's own 'exit' tag
  and excluding the six nameless mechanical templates.
- tracker.lua: scan, cache, navigation, announcements.

Caching keys on level name, player position and turn: position because
everything sorts by distance to the player, turn because creatures move and
containers empty. Scans run on keypress, never per frame.

FoV is respected throughout -- creatures only when currently visible, tiles when
visible or remembered -- so the tracker never becomes a cheat.

Home reports path length alongside the offset, via the game's own
calculatePathFromPlayer. Straight-line distance is misleading indoors, where a
chest three tiles north through a wall can be twenty steps away.

Corrects D4 in docs/05-decisions.md. I had claimed tile.tryInteract cleanly
separates 'the player can do something here' from scenery. It does not: 'wall'
carries a flavour-only tryInteractFunction ('You touch the wall. It's cold and
rough.'), so every wall segment was promoted into Interactables -- 13 in the
starting house, burying the chest and cauldron. Structural tiles
(blocksMovement and blocksVision) are now excluded before the tryInteract test;
containers and furniture block movement but not sight, so they survive.
12 kinds/19 instances instead of 13/32.

13/13 testbed checks, history unit tests passing.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

accessibility/docs/scratch.md

@@ -3,7 +3,7 @@
 **Read this first on any handoff.** Living document: update it whenever state changes, before ending a turn.
 
 Last updated: 2026-08-01 · Currently: **Phases 0–1 done, menus + dialogue done.
-Phase 2 (tile examination) next.**
+Phase 3 done. Phase 4 (remaining menus) next.**
 
 **Game is now playable start-to-finish by ear** from main menu through the intro
 conversation into gameplay — verified by the testbed, 9/9 checks.
@@ -127,6 +127,10 @@ needs a human at the keyboard — Talon to test.
 | `/` | Scan all 8 neighbours, clockwise from north (terse) |
 | `;` | Where am I — level, in-game time, coordinates |
 | `Ctrl`+numpad 1–9 | Probe that direction without moving (`Ctrl+kp5` = standing on) |
+| `Ctrl+PageUp` / `Ctrl+PageDown` | Tracker: previous / next **category** |
+| `PageUp` / `PageDown` | Tracker: previous / next **kind** |
+| `Shift+PageUp` / `Shift+PageDown` | Tracker: previous / next **instance** |
+| `Home` | Tracker: distance, direction and path length to current instance |
 
 Game keys worth knowing: **`x`** enters examine mode (not `e`), `f` finds exits
 while examining, `j` journal, `i` inventory, `c` character, `a` actions menu.
@@ -278,10 +282,56 @@ require time — reading its public fields is the decoupled route.)*
 `love.event.push`, so without this seam every modifier-gated hotkey would be
 untestable. The testbed swaps them per keypress.
 
+### Done — Phase 3: object tracker
+
+- `accessibility/categories.lua` — flag-first classification into the six
+  categories, plus the 6-template exclusion list and reuse of the game's `exit`
+  tag.
+- `accessibility/tracker.lua` — scan, cache, three-level navigation, announcements.
+
+Verified in the starting house:
+```
+Interactables, 12 kinds
+a bed, 1, nearest 1 tile south-west, 2 of 12
+an open door 1 of 1, 2 tiles north-west
+an open door, 2 tiles north-west, 2 steps by path      <- Home
+```
+
+**Caching:** signature is `level name : player x : player y : turn`. Position
+matters because everything sorts by distance; turn matters because creatures move
+and containers empty. Scans run on keypress only, never per frame.
+
+**FoV respected** — creatures only when currently visible, tiles when visible or
+remembered. The tracker never reveals what a sighted player couldn't see.
+
+**`Home` reports path length, not just offset.** Straight-line distance is badly
+misleading indoors: a chest 3 tiles north through a wall can be 20 steps away.
+Uses the game's own `calculatePathFromPlayer`.
+
+#### ⚠ Correction to D4 — `tryInteract` is NOT a clean "worth tracking" signal
+`wall` carries a **flavour-only** `tryInteractFunction` ("You touch the wall.
+It's cold and rough."), so flag-first classification promoted every wall segment
+into Interactables — 13 in the starting house, burying the chest and cauldron.
+**Fix: exclude structural tiles (`blocksMovement and blocksVision`) before the
+`tryInteract` test.** Containers and furniture block movement but not sight, so
+they survive. 13 kinds/32 instances → 12 kinds/19 instances.
+`docs/05-decisions.md` D4 has been amended.
+
+*(Not a bug: Items/Alchemy are empty in the tutorial house because
+`chest_tutorial` literally prints "find nothing of use for now" — it has no loot
+yet. Verify against a later area before trusting those two categories.)*
+
 ### Known gaps (next up)
-- **Phase 3: object tracker** — the headline feature, not started.
-- Wall tone retrigger fix not yet confirmed by ear.
-- `ingame` itself has no descriptor (player status: HP, statuses, current action).
+- **Phase 4**: descriptors for `worldmap`, `journal`, `character`, `research`,
+  `inventory`, `craft`, `refine`, `trade`, `actions_menu`, `alchemy_table`,
+  `keybindings_menu`, `config_menu`, `menu_text`, `ingame_message`,
+  `menu_message`. (`inventory`/`craft`/`refine`/`trade` are partly covered
+  already by the `inventoryCursorPopup` patch.)
+- **Phase 5**: player status key (HP, statuses, current action), popup
+  announcements, damage alerts, mod settings.
+- `ingame` itself has no descriptor.
+- Tracker categories Items/Alchemy/Exits/Creatures/Terrain unverified against a
+  populated area — the tutorial house has none of them.
 - `worldmap`, `journal`, `character`, `research`, `inventory`, `craft`, `refine`,
   `trade`, `actions_menu`, `alchemy_table`, `keybindings_menu`, `config_menu`,
   `menu_text`, `ingame_message`, `menu_message` still have no descriptors.