docs: mark simulation definitions phase complete

docs/PROJECT_CONTEXT.md

@@ -465,12 +465,14 @@ NpcVisual navigates through the active world
 │   ├── SimVillage.gd
 │   ├── SimulationClock.gd
 │   ├── SimulationManager.gd
+│   ├── definitions/           Stable IDs and custom definition resources
 │   └── state/                 Versioned simulation-state records
 ├── tests/
 │   ├── deterministic_simulation_test.gd
 │   ├── flat_map_baseline_test.gd
 │   ├── jajce_world_scaffold_test.gd
 │   ├── resource_node_player_parity_test.gd
+│   ├── simulation_definitions_test.gd
 │   └── simulation_state_serialization_test.gd
 ├── terrain/jajce/             Dedicated Terrain3D seed data and assets
 ├── tools/
@@ -495,7 +497,8 @@ NpcVisual navigates through the active world
 
 These are expected prototype constraints, not necessarily isolated bugs:
 
-- Task names and task-to-activity-marker mappings are duplicated strings.
+- Action and profession IDs are stable and definition-backed, but activity
+  marker mapping and several action effects remain hard-coded.
 - Temporary activity markers remain for eating, rest, study, and patrol; NPC
   and player food/wood gathering use `ResourceNode` instances with no fallback.
 - Current NPC, village, resource, clock, and RNG state serialize through schema
@@ -716,7 +719,7 @@ Food and wood migration and the deliberately minimal `JajceWorld` scaffold,
 greybox, navigation spike, and stable-ID placement proof are complete. Do not
 proceed directly from that proof into open-ended beauty production.
 
-The architecture gate is now the active milestone. Its first three slices are
+The architecture gate is now the active milestone. Its first four slices are
 complete:
 
 - explicit fixed-step simulation clock;
@@ -725,11 +728,12 @@ complete:
 - versioned JSON records for NPC, village, resource, clock, and RNG state;
 - deterministic save/restore continuation with exact 64-bit RNG preservation;
 - simulation-owned resource amount/reservation state with ResourceNode
-  presentation binding and unload/rebind coverage.
+  presentation binding and unload/rebind coverage;
+- stable StringName action/profession IDs plus validated custom definition
+  resources used by simulation, targeting, generation, and persistence.
 
 The remaining gate work is:
 
-- data-defined action and profession IDs;
 - separated action selection, execution, target resolution, and visual travel;
 - explicit synchronization of active NPC position.