feat: District Portals API (DB-based, no hardcodes)

Backend:
- GET /api/v1/districts - list all districts from DB
- GET /api/v1/districts/{slug} - district detail with lead agent, core team, rooms, nodes

repo_city methods:
- get_districts() - SELECT FROM microdaos WHERE dao_type='district'
- get_district_by_slug()
- get_district_lead_agent() - with fallback to orchestrator
- get_district_core_team()
- get_district_agents()
- get_district_rooms() - by slug prefix
- get_district_nodes()
- get_district_stats()

Task doc: TASK_PHASE_DISTRICT_PORTALS_v1.md

services/city-service/routes_city.py

@@ -1123,6 +1123,142 @@ async def get_city_room_by_slug(slug: str):
         raise HTTPException(status_code=500, detail="Failed to get city room")
 
 
+# =============================================================================
+# Districts API (DB-based, no hardcodes)
+# =============================================================================
+
+@api_router.get("/districts")
+async def get_districts():
+    """
+    Отримати список всіх District-ів.
+    District = microdao з dao_type = 'district'
+    """
+    try:
+        districts = await repo_city.get_districts()
+        
+        result = []
+        for d in districts:
+            # Get lead agent for each district
+            lead_agent = await repo_city.get_district_lead_agent(d["id"])
+            
+            # Get rooms count
+            rooms = await repo_city.get_district_rooms(d["slug"])
+            
+            result.append({
+                "id": d["id"],
+                "slug": d["slug"],
+                "name": d["name"],
+                "description": d.get("description"),
+                "dao_type": d["dao_type"],
+                "lead_agent": {
+                    "id": lead_agent["id"],
+                    "name": lead_agent["name"],
+                    "avatar_url": lead_agent.get("avatar_url")
+                } if lead_agent else None,
+                "rooms_count": len(rooms),
+                "rooms": [{"id": r["id"], "slug": r["slug"], "name": r["name"]} for r in rooms[:3]]
+            })
+        
+        return result
+    except Exception as e:
+        logger.error(f"Failed to get districts: {e}")
+        raise HTTPException(status_code=500, detail="Failed to get districts")
+
+
+@api_router.get("/districts/{slug}")
+async def get_district_detail(slug: str):
+    """
+    Отримати деталі District-а за slug.
+    """
+    try:
+        district = await repo_city.get_district_by_slug(slug)
+        if not district:
+            raise HTTPException(status_code=404, detail=f"District not found: {slug}")
+        
+        # Get lead agent
+        lead_agent = await repo_city.get_district_lead_agent(district["id"])
+        
+        # Get core team
+        core_team = await repo_city.get_district_core_team(district["id"])
+        
+        # Get all agents
+        agents = await repo_city.get_district_agents(district["id"])
+        
+        # Get rooms
+        rooms = await repo_city.get_district_rooms(district["slug"])
+        
+        # Get nodes
+        nodes = await repo_city.get_district_nodes(district["id"])
+        
+        # Get stats
+        stats = await repo_city.get_district_stats(district["id"], district["slug"])
+        
+        return {
+            "district": {
+                "id": district["id"],
+                "slug": district["slug"],
+                "name": district["name"],
+                "description": district.get("description"),
+                "dao_type": district["dao_type"]
+            },
+            "lead_agent": {
+                "id": lead_agent["id"],
+                "name": lead_agent["name"],
+                "kind": lead_agent.get("kind"),
+                "status": lead_agent.get("status"),
+                "avatar_url": lead_agent.get("avatar_url"),
+                "gov_level": lead_agent.get("gov_level")
+            } if lead_agent else None,
+            "core_team": [
+                {
+                    "id": a["id"],
+                    "name": a["name"],
+                    "kind": a.get("kind"),
+                    "status": a.get("status"),
+                    "avatar_url": a.get("avatar_url"),
+                    "role": a.get("membership_role")
+                } for a in core_team
+            ],
+            "agents": [
+                {
+                    "id": a["id"],
+                    "name": a["name"],
+                    "kind": a.get("kind"),
+                    "status": a.get("status"),
+                    "avatar_url": a.get("avatar_url"),
+                    "role": a.get("membership_role"),
+                    "is_core": a.get("is_core", False)
+                } for a in agents
+            ],
+            "rooms": [
+                {
+                    "id": r["id"],
+                    "slug": r["slug"],
+                    "name": r["name"],
+                    "description": r.get("description"),
+                    "matrix_room_id": r.get("matrix_room_id"),
+                    "room_role": r.get("room_role"),
+                    "is_public": r.get("is_public", True)
+                } for r in rooms
+            ],
+            "nodes": [
+                {
+                    "id": n["id"],
+                    "name": n["name"],
+                    "kind": n.get("kind"),
+                    "status": n.get("status"),
+                    "location": n.get("location")
+                } for n in nodes
+            ],
+            "stats": stats
+        }
+    except HTTPException:
+        raise
+    except Exception as e:
+        logger.error(f"Failed to get district {slug}: {e}")
+        raise HTTPException(status_code=500, detail="Failed to get district")
+
+
 @router.get("/rooms/{room_id}", response_model=CityRoomDetail)
 async def get_city_room(room_id: str):
     """