feat: Add resource search and dungeon room description commands

- Implemented `resource-search` command to allow fuzzy searching of resource labels.
- Added `dungeon-describe-room` command to summarize metadata for a specified dungeon room.
- Enhanced `agent` command handler to support new commands and updated usage documentation.
- Introduced read-only accessors for room metadata in the Room class.
- Updated AI service to recognize and handle new commands for resource searching and room description.
- Improved metrics tracking for user interactions, including command execution and response times.
- Enhanced TUI to display command metrics and session summaries.

src/app/zelda3/dungeon/room.h

@@ -313,6 +313,15 @@ class Room {
   void SetStair3Target(uint8_t target) { stair3_.target = target; }
   void SetStair4Target(uint8_t target) { stair4_.target = target; }
 
+  // Read-only accessors for metadata
+  EffectKey effect() const { return effect_; }
+  TagKey tag1() const { return tag1_; }
+  TagKey tag2() const { return tag2_; }
+  CollisionKey collision() const { return collision_; }
+  const LayerMergeType& layer_merging() const { return layer_merging_; }
+
+  int id() const { return room_id_; }
+
   uint8_t blockset = 0;
   uint8_t spriteset = 0;
   uint8_t palette = 0;