# Handoff Report — worker_m3_fix

## 1. Observation
- In `server/world/wilderness_map_generator.py` (lines 67-76):
  `WildernessMapGenerator.for_zone` looked up `defn = get_biome_definition(str(biome_id))` and set `b_id = defn.biome_id`. When `biome_id` was a style alias such as `'STY_02_HUYET_SAT_LAM'`, `defn.biome_id` returned the canonical biome id `'CRIMSON_BLOOD_FOREST'`, which broke `assert gen.biome_id == target_style.style_id` in `tests/e2e/test_30_biomes_generation_e2e.py::TestZoneCanonicalBiomeResolution::test_explicit_biome_override_on_zone`.
- In `client/webapp/js/engine/tile_map_renderer.js` (line 294):
  `_drawTile()` called `ctx.drawImage(propSprite, px - 8, py - 10, 16, 16)` using the 5-argument form, squashing the entire 192x64 composite props sheet (3 frames of 64x64) into a single 16x16 destination area instead of slicing a single 64x64 sprite frame.
- In `client/webapp/js/engine/biome_texture_manager.js` (lines 280-286):
  `BiomeTextureManagerClass` defined `getPropSprite(biomeCode, propId)` but lacked the `getPropDecal(biomeCode, propId)` alias expected by consumers and unit test suite `tests/unit/test_biome_texture_manager.js`.
- File length and syntax checks:
  - `server/world/wilderness_map_generator.py`: 320 lines (Soft Cap <= 350, Hard Cap <= 500). Max function length <= 50 lines.
  - `client/webapp/js/engine/tile_map_renderer.js`: 330 lines (Soft Cap <= 350, Hard Cap <= 500).
  - `client/webapp/js/engine/biome_texture_manager.js`: 302 lines (Soft Cap <= 350, Hard Cap <= 500).

## 2. Logic Chain
- For Finding 1:
  In `WildernessMapGenerator.for_zone()`, integer or numeric string biomes are resolved to integer codes via `get_biome_by_code(int(biome_id))`. When `biome_id` is a string identifier, preserving `b_id = str(biome_id)` directly ensures that custom style IDs (like `STY_02_HUYET_SAT_LAM`) remain intact on `gen.biome_id`. Later, when `gen.generate()` runs, `get_biome_definition(self.biome_id)` handles alias resolution through `BIOME_ALIASES.get(biome_id, biome_id)` without mutating the instance's `biome_id` attribute.
- For Finding 2:
  The composite prop sheet consists of 3 horizontal frames, each 64x64 pixels (total dimensions 192x64). By computing `frameIdx = Math.floor(rnd * 20) % 3` and invoking `ctx.drawImage(propSprite, frameIdx * 64, 0, 64, 64, px - 8, py - 10, 16, 16)`, the renderer samples exactly one 64x64 frame and renders it to the tile coordinate `(px - 8, py - 10, 16, 16)` with deterministic variance across tiles.
- For Finding 3:
  Adding `getPropDecal(biomeCode, propId)` to `BiomeTextureManagerClass` that delegates directly to `this.getPropSprite(biomeCode, propId)` provides API symmetry between decal queries and sprite queries without code duplication or state leakage.

## 3. Caveats
- `tools/lint/check_code_and_doc_hygiene.py --strict` reports 2 pre-existing repo-wide file length violations in unrelated files: `client/webapp/js/data/i18n.js` (582 lines) and `tools/knowledge/combat_room_sync.py` (581 lines). These files are strictly outside the exclusive write boundaries of this task and remain untouched. All 3 modified files in this assignment (`wilderness_map_generator.py`, `tile_map_renderer.js`, `biome_texture_manager.js`) strictly adhere to the <= 350 line soft cap and AST function length bounds.
- No caveats on functional behavior or test regressions.

## 4. Conclusion
- All 3 findings identified by Reviewers M3-1, M3-2, and Challenger M3-1 have been cleanly resolved within the assigned exclusive write boundaries.
- 100% test pass rate achieved across unit tests, E2E tests, and empirical stress harnesses.

## 5. Verification Method
Execute the following verification commands from the project root (`c:\Projects\FreeExile`):

1. **Pytest Suite (Procedural Map, Biomes, War Fog, Wilderness)**:
   ```bash
   pytest tests/e2e/test_30_biomes_generation_e2e.py tests/unit/test_wilderness_map_generator.py tests/unit/test_war_fog_and_procedural_map.py -v
   ```
   *Result*: 62 passed in ~4.0s (100% pass rate).

2. **Node.js Unit Test Suite (Biome Texture Manager)**:
   ```bash
   node tests/unit/test_biome_texture_manager.js
   ```
   *Result*: 8 / 8 test sections passed empirically.

3. **Node.js Challenger Stress Suites**:
   ```bash
   node tests/unit/test_challenger_biome_texture_stress.js
   node tests/unit/test_challenger_tile_grid_stress.js
   node tests/unit/test_challenger_lru_thrashing_stress.js
   ```
   *Result*: All suites passed cleanly with 0 memory leaks and 0 errors.

4. **Code Hygiene & Function Length Audit on Target Files**:
   ```powershell
   pwsh -Command "(Get-Content server/world/wilderness_map_generator.py).Count; (Get-Content client/webapp/js/engine/tile_map_renderer.js).Count; (Get-Content client/webapp/js/engine/biome_texture_manager.js).Count"
   ```
   *Result*: 320, 330, and 302 lines respectively (all <= 350 soft cap).