feat: Add Codex screen for recording discovered living entities

[Copilot]

Adds a Codex that tracks which living entity types (Bear, Chicken) the player has encountered, with persistence across save/load and a dedicated screen accessible via configurable keybinding and the options menu.

Codex data model

• src/codex/codex.py — @component class maintaining a set of discovered entity class names with discover(), hasDiscovered(), getDiscoveredEntities() (sorted)
• src/codex/codex.py also centralizes ALL_LIVING_ENTITY_TYPES and ENTITY_IMAGE_PATHS as the single source of truth for the entity roster
• src/codex/codexJsonReaderWriter.py — JSON persistence following the Stats pattern, with graceful error handling for corrupted save files
• schemas/codex.json — validation schema

Discovery trigger

• WorldScreen resolves Codex via DI, calls discoverLivingEntitiesInRoom() after room transitions and on initialization
• First discovery of a new type shows "New codex entry: Bear" via status.set() and saves immediately

Keybinding & navigation

• codex action added to KeyBindings.DEFAULT_BINDINGS (default pygame.K_l) with label for Controls screen remapping
• CODEX_SCREEN added to ScreenType, handled in WorldScreen.handleKeyDownEvent() and Roam.run()
• Codex is also reachable via a "Codex" button in the options menu
• Context-aware back navigation: returns to Options when opened from the menu, or to the World when opened via keybinding

Codex screen

• src/screen/codexScreen.py — @component screen consistent with ControlsScreen layout: scrollable entity list with textures for discovered entries, "???" dimmed for undiscovered, Back button, mouse wheel scrolling
• Entity names are left-aligned after sprites to prevent overlap at any window size
• Font and image objects are cached to avoid per-frame recreation overhead

Persistence integration

• Codex loaded in WorldScreen.initialize() alongside stats/tick/inventory
• Codex saved in saveSynchronous() on world exit

Tests

• 19 new tests: Codex data model, persistence round-trip, schema validation, CodexScreen behavior, scroll bounds, and return-screen routing

[Copilot]

Pull request overview

Adds a new “Codex” feature that records which living entity types the player has encountered, persists that data in saves, and provides a dedicated Codex UI screen accessible via a configurable keybinding.

Changes:

• Introduces Codex model + JSON persistence + schema validation for save/load.
• Adds CodexScreen UI and wires it into the screen routing / keybinding system.
• Hooks entity discovery into WorldScreen (initialization + room transitions) and persists codex state on exit / first discovery.

Reviewed changes

Copilot reviewed 12 out of 13 changed files in this pull request and generated 6 comments.

Show a summary per file

File	Description
src/codex/codex.py	New DI-registered Codex model tracking discovered entity types.
src/codex/codexJsonReaderWriter.py	Adds codex save/load JSON persistence with schema validation.
schemas/codex.json	New JSON schema for codex save data.
src/screen/codexScreen.py	New Codex UI screen with scrollable list and entity textures.
src/screen/screenType.py	Adds CODEX_SCREEN screen type constant.
src/screen/worldScreen.py	Discovers living entities on init/room change; loads/saves codex with the save set.
src/roam.py	Resolves and routes to CodexScreen based on ScreenType.CODEX_SCREEN.
src/config/keyBindings.py	Adds codex action default binding (K_l) and label for remapping UI.
tests/codex/test_codex.py	Unit tests for Codex behavior and persistence round-trip.
tests/codex/test_codexScreen.py	Unit tests for CodexScreen basic behavior and scrolling.
README.md	Documents the new default Codex keybinding.
CHANGELOG.md	Records the new Codex feature and adds a learning-log entry.
src/codex/__init__.py	Package init file for the new codex module.

[Copilot]

ALL_LIVING_ENTITY_TYPES / ENTITY_IMAGE_PATHS are hardcoded in the screen, so adding a new living entity type requires updating multiple places and the codex UI can easily fall out of sync with the actual entity roster. Consider centralizing the roster (e.g., in codex module) or deriving it from an existing registry used for living entities so there’s a single source of truth.

[Copilot]

load() performs schema validation without handling validation errors. A corrupted/edited codex.json will currently raise and prevent the world from loading. Consider catching jsonschema.exceptions.ValidationError / json.JSONDecodeError, logging the problem, and returning None (or an empty list) so the game can still start.

[Copilot]

Unused import: patch is imported but never referenced. Removing it keeps the test module clean and avoids lint/static-analysis noise.

Suggested change

	from unittest.mock import MagicMock, patch
	from unittest.mock import MagicMock

[Copilot]

visibleRows can become 0 (or negative) if the window height is small, which makes maxOffset/scrollInfo calculations inconsistent (e.g., showing ranges like 3-2 of 2). Guard by ensuring visibleRows is at least 1, or skip rendering/clamping logic when there’s no vertical space to show rows.

Suggested change

	visibleRows = int((y - startY - 80) / rowHeight)
	visibleRows = max(1, int((y - startY - 80) / rowHeight))

[dmccoystephenson]

@copilot You are a coding agent tasked with resolving all open comments and review threads
on this pull request. Work through every comment systematically and apply the
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[Copilot]

@copilot You are a coding agent tasked with resolving all open comments and review threads
on this pull request. Work through every comment systematically and apply the
appropriate code changes....

All 6 review comments addressed in f094246:

1. Centralized entity roster — Moved ALL_LIVING_ENTITY_TYPES and ENTITY_IMAGE_PATHS from codexScreen.py to codex.py as the single source of truth. Screen imports from the codex module.
2. Save error handling — save() now catches ValidationError and logs instead of crashing, matching the inventoryJsonReaderWriter pattern.
3. Load error handling — load() now catches json.JSONDecodeError and ValidationError, logs the error, and returns None so a corrupted file won't prevent the game from starting.
4. Removed unused import — Removed patch from test_codexScreen.py.
5. Specific exception handling — Replaced blanket Exception in _getEntityImage() with (pygame.error, FileNotFoundError) and added logging via getLogger().
6. Guard visibleRows — Changed to max(1, int(...)) to prevent zero/negative row counts on small windows.

All 381 tests pass.

[dmccoystephenson]

@copilot The Codex should be reachable via the options menu. Additionally, please ensure that the entity names and entity sprites don't overlap in the Codex screen.

[Copilot]

@copilot The Codex should be reachable via the options menu. Additionally, please ensure that the entity names and entity sprites don't overlap in the Codex screen.

Both changes addressed in b59acc2:

Options menu access — Added a "Codex" button to the options menu (between Controls and Back). Navigation is context-aware: pressing Back/Escape returns to Options when opened from the menu, or to the World when opened via the L keybinding.

Sprite/text overlap fix — Entity names are now left-aligned starting 16px after the right edge of the sprite image, using a new _drawTextLeftAligned() method instead of the center-aligned drawText(). This prevents text from overlapping sprites regardless of name length.