feat(city-map): Add 2D City Map with coordinates and agent presence

- Add migration 013_city_map_coordinates.sql with map coordinates, zones, and agents table
- Add /city/map API endpoint in city-service
- Add /city/agents and /city/agents/online endpoints
- Extend presence aggregator to include agents[] in snapshot
- Add AgentsSource for fetching agent data from DB
- Create CityMap component with interactive room tiles
- Add useCityMap hook for fetching map data
- Update useGlobalPresence to include agents
- Add map/list view toggle on /city page
- Add agent badges to room cards and map tiles

services/matrix-presence-aggregator/app/models.py

@@ -1,19 +1,31 @@
 """Data models for Presence Aggregator"""
 from pydantic import BaseModel
-from typing import List
+from typing import List, Optional
 from datetime import datetime
 
 
+class AgentPresence(BaseModel):
+    """Agent presence in a room"""
+    agent_id: str
+    display_name: str
+    kind: str = "assistant"  # assistant, civic, oracle, builder
+    status: str = "offline"  # online, offline, busy
+    room_id: Optional[str] = None
+    color: Optional[str] = None
+
+
 class RoomPresence(BaseModel):
     room_id: str          # internal room id from DB
     matrix_room_id: str   # Matrix room ID (!xxx:domain)
     online: int
     typing: int
+    agents: List[AgentPresence] = []  # Agents present in this room
 
 
 class CityPresence(BaseModel):
     online_total: int
     rooms_online: int
+    agents_online: int = 0
 
 
 class PresenceSnapshot(BaseModel):
@@ -21,4 +33,6 @@ class PresenceSnapshot(BaseModel):
     timestamp: datetime
     city: CityPresence
     rooms: List[RoomPresence]
+    agents: List[AgentPresence] = []  # All online agents
+