Feature: Ratings, Lightbox, Forum-Standort, Notifications, Routen-Recording, Chat-Picker

- Bewertungssystem (ratings.py): Sterne für Sitter/Walks/Places/Routen
- Admin: Server-Log-Viewer + OSM-Cache-Statistiken
- Chat: "Neue Nachricht"-Button mit Freundesliste-Picker
- Forum: 5 neue Kategorien, Standorteingabe (locationPicker), Absende-Toast, Lightbox
- Freunde: Aktivitäts-Filter (Chips), Freundschaftsanfrage → In-App-Notification
- Sitter: locationPicker statt manuelle Koordinateneingabe + ratingStars
- Tagebuch: Bilder-Lightbox im Detail-View, iOS-Modal-Header-Fix (90svh)
- Routen: Start/Stopp-Button wechselt Zustand, nutzt Page_map.isRecording()
- Benachrichtigungen: Delete-Button sichtbar, typ-basierte Navigation, Toast-Feedback
- OSM: globales Semaphore + 429-Retry-Logic; Scheduler: München-Umland, täglich
- SW by-v225, APP_VER 202

backend/routes/osm.py

@@ -20,6 +20,9 @@ CACHE_ZOOM   = 12
 CACHE_DAYS   = 14
 OVERPASS_URL = 'https://overpass-api.de/api/interpreter'
 
+# Globales Limit: max 2 gleichzeitige Overpass-Anfragen (Prewarm + User geteilt)
+_overpass_sem = asyncio.Semaphore(2)
+
 OSM_QUERIES = {
     'waste_basket':   '[out:json][timeout:20];node["amenity"="waste_basket"]({bbox});out;',
     'dog_park':       '[out:json][timeout:25];(way["leisure"="dog_park"]({bbox});node["leisure"="dog_park"]({bbox});way["leisure"="park"]["dog"="yes"]({bbox});node["leisure"="park"]["dog"="yes"]({bbox}););out center;',
@@ -61,10 +64,17 @@ def _covering_tiles(south, west, north, east, zoom):
 # Overpass-Fetch + Cache
 # ------------------------------------------------------------------
 async def _fetch_overpass(query):
-    async with httpx.AsyncClient(timeout=40) as client:
-        r = await client.post(OVERPASS_URL, data={'data': query})
-        r.raise_for_status()
-        return r.json().get('elements', [])
+    for attempt in range(3):
+        async with _overpass_sem:
+            async with httpx.AsyncClient(timeout=40) as client:
+                r = await client.post(OVERPASS_URL, data={'data': query})
+                if r.status_code != 429:
+                    r.raise_for_status()
+                    return r.json().get('elements', [])
+                logger.warning(f"Overpass 429 (Versuch {attempt + 1}/3)")
+        # Semaphore freigeben, dann warten
+        await asyncio.sleep(45 * (attempt + 1))
+    raise Exception("Overpass 429 nach 3 Versuchen")
 
 def _stale_tiles(poi_type, tiles):
     stale = []
@@ -143,11 +153,7 @@ async def get_pois(
         stale = _stale_tiles(type, tiles)
 
         if stale and not fast:
-            sem = asyncio.Semaphore(3)
-            async def _limited(x, y):
-                async with sem:
-                    await _fetch_and_store_tile(type, x, y)
-            await asyncio.gather(*[_limited(x, y) for (x, y) in stale])
+            await asyncio.gather(*[_fetch_and_store_tile(type, x, y) for (x, y) in stale])
             fetched_fresh = True
 
         with db() as conn:
@@ -313,12 +319,8 @@ async def analyze_region(
     tiles = _covering_tiles(south, west, north, east, CACHE_ZOOM)
 
     async def _warmup():
-        sem = asyncio.Semaphore(3)
-        async def _limited(poi_type, x, y):
-            async with sem:
-                await _fetch_and_store_tile(poi_type, x, y)
         tasks = [
-            _limited(pt, x, y)
+            _fetch_and_store_tile(pt, x, y)
             for pt in OSM_QUERIES
             for (x, y) in _stale_tiles(pt, tiles)
         ]