feat(simulation): smuggler inventory — CarriedBy, Take/Place verbs (#424)

Implement physical inventory system per D-065:

- CarriedBy(StableId) component marks items as carried by an entity
- ItemName and InventorySlot components for display and slot assignment
- Take verb: removes TilePosition, adds CarriedBy + InventorySlot
- Place verb: removes CarriedBy + InventorySlot, adds TilePosition
- Observer snapshot populates player_inventory from carried items query
- Info boundary: carried items lack TilePosition, naturally excluded
  from all spatial queries (visibility, interactions) for other entities
- 9-slot capacity (3x3 grid per OQ-24), auto-assigns first free slot
- 8 new tests covering take, place, sequential slots, full rejection

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

server/src/perception/observer/mod.rs

@@ -15,6 +15,7 @@ use crate::knowledge::{EntityRegistry, KnowledgeGraph, StableId};
 use crate::perception::query::{ActivePerceptionMode, VisibilityGeometry};
 use crate::perception::vision_cone::Facing;
 use crate::simulation::interaction::NearbyInteractionBuffer;
+use crate::simulation::inventory::{CarriedBy, InventorySlot, ItemName};
 use crate::simulation::monologue::MonologueBuffer;
 use crate::simulation::movement::{PlayerCharacter, TilePosition, WalkabilityMap};
 use crate::simulation::stance::Stance;
@@ -52,7 +53,7 @@ pub fn compute_observer_snapshot(
     geometry: Res<VisibilityGeometry>,
     registry: Res<EntityRegistry>,
     mut observer_query: Query<
-        (&TilePosition, Option<&Facing>, &KnowledgeGraph, &mut NearbyInteractionBuffer, &mut MonologueBuffer, Option<&Stance>, Option<&CharacterArchetype>),
+        (Entity, &TilePosition, Option<&Facing>, &KnowledgeGraph, &mut NearbyInteractionBuffer, &mut MonologueBuffer, Option<&Stance>, Option<&CharacterArchetype>),
         With<PlayerCharacter>,
     >,
     all_entities: Query<(
@@ -61,9 +62,10 @@ pub fn compute_observer_snapshot(
         Option<&PlayerCharacter>,
         Option<&crate::npc::Npc>,
     )>,
+    inventory_items: Query<(Entity, &CarriedBy, &ItemName, &InventorySlot)>,
     mut buffer: ResMut<SnapshotBuffer>,
 ) {
-    let Ok((_observer_pos, facing_opt, observer_kg, mut interaction_buffer, mut monologue_buffer, stance_opt, archetype_opt)) =
+    let Ok((observer_entity, _observer_pos, facing_opt, observer_kg, mut interaction_buffer, mut monologue_buffer, stance_opt, archetype_opt)) =
         observer_query.single_mut()
     else {
         return;
@@ -75,6 +77,18 @@ pub fn compute_observer_snapshot(
 
     let archetype = archetype_opt.copied().unwrap_or_default();
 
+    // Collect player inventory (D-065 info boundary: only own items)
+    let player_inventory = registry
+        .to_stable(observer_entity)
+        .map(|player_sid| {
+            crate::simulation::inventory::collect_inventory_for(
+                player_sid,
+                &inventory_items,
+                &registry,
+            )
+        })
+        .unwrap_or_default();
+
     let (mut entities, visible_ids) =
         filter_visible_entities(&geometry, &registry, observer_kg, &all_entities);
 
@@ -114,7 +128,7 @@ pub fn compute_observer_snapshot(
         game_time,
         player_facing: facing,
         player_stance: stance_opt.map(|s| s.0).unwrap_or_default(),
-        player_inventory: Vec::new(),
+        player_inventory,
         entities,
         visible_tiles: geometry.visible_tiles.clone(),
         nearby_interactions,