Fix: NoneType.upper() Fehler bei country_code=None im Geoparsing

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

src/agents/geoparsing.py

@@ -60,7 +60,7 @@ def _geocode_offline(name: str, country_code: str = "") -> Optional[dict]:
     if matches:
         # Disambiguierung: country_code bevorzugen, dann Population
         if country_code:
-            cc_matches = [c for c in matches if c.get("countrycode", "").upper() == country_code.upper()]
+            cc_matches = [c for c in matches if c.get("countrycode", "").upper() == (country_code or "").upper()]
             if cc_matches:
                 matches = cc_matches
         best = max(matches, key=lambda c: c.get("population", 0))
@@ -95,7 +95,7 @@ def _geocode_location(name: str, country_code: str = "", haiku_coords: Optional[
         country_code: ISO-2 Code (von Haiku)
         haiku_coords: {"lat": float, "lon": float} (Fallback von Haiku)
     """
-    cache_key = f"{name.lower().strip()}|{country_code.upper()}"
+    cache_key = f"{name.lower().strip()}|{(country_code or '').upper()}"
     if cache_key in _geocode_cache:
         return _geocode_cache[cache_key]