feat: add provenance-aware npc communication

docs/PROJECT_CONTEXT.md

@@ -414,8 +414,9 @@ Focused `RefCounted` collaborators keep rule ownership visible:
 - `VillageEconomy` owns storage/inventory transactions and synchronized
   village resource views;
 - `SimulationEventLog` owns deterministic event history and queries;
-- `EventKnowledgeSystem` owns per-NPC known-event references and captures
-  actor/nearby evidence when a witnessable event is recorded;
+- `EventKnowledgeSystem` owns per-NPC known-event references, immutable
+  first-acquisition provenance, actor/nearby evidence capture, and bounded
+  one-hop communication;
 - `RelationshipSystem` owns directed relationship state, event-driven trust
   consequences, and deterministic social queries.
 
@@ -476,6 +477,7 @@ NpcVisual navigates through the active world
     |       |
     |       v
     |   SimulationManager marks NPC as working
+    |       -> at a shared activity, one nearby worker may communicate one direct fact
     |       |
     |       v
     |   Later ticks complete work
@@ -521,12 +523,13 @@ NpcVisual navigates through the active world
 │   ├── definitions/           Stable IDs and custom definition resources
 │   ├── economy/               Inventory and storage transactions
 │   ├── events/                Ordered event history and queries
-│   ├── knowledge/             Per-NPC references to known objective events
+│   ├── knowledge/             Per-NPC facts, provenance, and bounded transfer
 │   ├── persistence/           Validated local save-slot storage
 │   ├── relationships/         Directed social consequences and queries
 │   └── state/                 Versioned simulation-state records
 ├── tests/
 │   ├── action_system_boundaries_test.gd
+│   ├── communicated_knowledge_consequence_test.gd
 │   ├── deterministic_simulation_test.gd
 │   ├── food_storage_loop_test.gd
 │   ├── jajce_world_scaffold_test.gd
@@ -568,7 +571,7 @@ These are expected prototype constraints, not necessarily isolated bugs:
   gathering use `ResourceNode` instances with no fallback, food transfer uses
   the typed pantry `StorageNode`, and patrol/study/rest use `ActivitySite`.
 - Current NPC, village, resource, storage, event, knowledge, relationship,
-  clock, and RNG state serialize through world schema v5. F5/F9 provide one
+  clock, and RNG state serialize through world schema v6. F5/F9 provide one
   validated local quicksave; a save menu, metadata, and player-transform
   persistence remain deferred.
 - Simulation-owned resource records retain live amounts, reservations, and
@@ -582,12 +585,13 @@ These are expected prototype constraints, not necessarily isolated bugs:
   village storage. Other village metrics remain aggregate values rather than
   located items.
 - NPCs have home positions, schedule periods, carried food/wood, and directed
-  familiarity/trust. They can retain direct proximity-witness knowledge of a
-  food deposit, but do not yet have wider social dimensions, goals, line of
-  sight/hearing evidence, memory decay, false beliefs, or communication.
-- The reason inspector exposes current decisions, utility rejections, and one
-  exact relationship cause plus the latest known fact, but deeper historical
-  decision traces are not yet retained.
+  familiarity/trust. They retain direct or one-hop communicated knowledge of a
+  food deposit with first-acquisition provenance, but do not yet have wider
+  social dimensions, goals, line-of-sight/hearing evidence, importance/decay,
+  false beliefs, or multi-hop rumours.
+- The reason inspector exposes current decisions, utility rejections, one exact
+  relationship cause, and the latest known fact with its speaker when
+  communicated, but deeper historical decision traces are not yet retained.
 - Active navigation is used as if all agents are local; no simulation LOD exists.
 - Unloaded traveling NPCs preserve their state but do not yet advance through
   abstract travel time.
@@ -827,10 +831,12 @@ simulation-garden runtime capture are complete.
 
 The first relationship and knowledge consequences are also complete:
 food-deposit events become separate known facts for their actor and nearby
-living NPCs; only an informed hungry familiar NPC gains directed trust. The
-exact event remains visible as both known fact and relationship cause, and that
-trust can redirect ordinary work toward helping a starving acquaintance. One
-provenance-aware NPC-to-NPC fact transfer is the next systems slice.
+living NPCs; only an informed hungry familiar NPC gains directed trust. At a
+shared non-storage activity, an already-working direct knower can tell one fact
+to an arriving nearby villager. The same event remains visible as known fact
+and relationship cause, the inspector names the speaker, and the listener's
+future work can change without duplicating event history. Importance and
+retention for known facts is the next systems slice.
 
 The remaining simulation-garden target still aims for: