feat(weather): romanise non-Latin place names before geocoding

Open-Meteo's geocoder only matches Latin/English spellings, so a Korean city
name like "서울" returns zero results even though the place exists. With
OUTPUT_LANGUAGE locked to Korean the tool-calling model naturally fills
`location` with the Korean name, which dead-ended on every weather request
("could not find location").

When the first geocode is empty and the name is non-ASCII, ask the warm small
model for the common English exonym ("서울" -> "Seoul") and retry once. ASCII
names skip the round-trip entirely.

Live-verified: "서울 날씨 알려줘" now returns real Seoul weather. Tests cover the
romanise-and-retry path and the ASCII short-circuit.

src/jarvis/tools/builtin/weather.py

@@ -83,6 +83,65 @@ def _extract_place_from_user_text(text: str, cfg) -> Optional[str]:
     return place
 
 
+def _romanise_place(name: str, cfg) -> Optional[str]:
+    """Romanise a non-Latin place name for the geocoder.
+
+    Open-Meteo's geocoding API only matches Latin/English spellings, so a
+    Korean (or other non-Latin) city name like ``서울`` returns zero results
+    even though the place plainly exists. When OUTPUT_LANGUAGE locks replies to
+    Korean the tool-calling model naturally fills ``location`` with the Korean
+    name, which would otherwise dead-end. Ask the (already warm) small model for
+    the common English exonym so geocoding can succeed on a retry.
+
+    Returns the romanised name, or ``None`` if it is unavailable, unchanged, or
+    doesn't look like a place.
+    """
+    if not isinstance(name, str) or not name.strip() or name.isascii():
+        return None
+    if cfg is None:
+        return None
+
+    model = (
+        getattr(cfg, "tool_router_model", "")
+        or getattr(cfg, "intent_judge_model", "")
+        or getattr(cfg, "ollama_chat_model", "")
+    )
+    base_url = getattr(cfg, "ollama_base_url", "")
+    if not model or not base_url:
+        return None
+
+    try:
+        from ...llm import call_llm_direct
+    except Exception:
+        return None
+
+    sys_prompt = (
+        "You romanise place names for a geocoding API that only understands "
+        "English/Latin spellings. Reply with ONLY the common English name of "
+        "the place, no punctuation, quotes, or explanation. "
+        "Examples: 서울 -> Seoul, 도쿄 -> Tokyo, 뮌헨 -> Munich."
+    )
+    user_prompt = f"Place: {name}\n\nEnglish name:"
+
+    try:
+        resp = call_llm_direct(
+            base_url, model, sys_prompt, user_prompt,
+            timeout_sec=float(getattr(cfg, "llm_tools_timeout_sec", 8.0)),
+        )
+    except Exception as e:
+        debug_log(f"    ⚠️ place romanisation failed: {e}", "tools")
+        return None
+
+    if not resp or not isinstance(resp, str):
+        return None
+    out = resp.strip().strip("'\"`*.,:;!?()[]{}<>").split("\n", 1)[0].strip()
+    if not out or out.lower() in _NO_PLACE_SENTINELS:
+        return None
+    if len(out) > 60 or len(out.split()) > 5 or out == name:
+        return None
+    return out
+
+
 # WMO Weather interpretation codes
 # https://open-meteo.com/en/docs
 WMO_CODES = {
@@ -274,6 +333,23 @@ class WeatherTool(Tool):
                 geo_response.raise_for_status()
                 geo_data = geo_response.json()
 
+                # Open-Meteo only matches Latin spellings, so a non-Latin name
+                # (e.g. Korean "서울") returns nothing. Retry once with an
+                # LLM-romanised name before giving up.
+                if not geo_data.get("results"):
+                    romanised = _romanise_place(location_str, getattr(context, "cfg", None))
+                    if romanised:
+                        debug_log(
+                            f"    🌤️ geocode empty for '{location_str}'; retrying romanised '{romanised}'",
+                            "tools",
+                        )
+                        geocode_params["name"] = romanised
+                        geo_response = requests.get(geocode_url, params=geocode_params, timeout=10)
+                        geo_response.raise_for_status()
+                        geo_data = geo_response.json()
+                        if geo_data.get("results"):
+                            location_str = romanised
+
                 if not geo_data.get("results"):
                     return ToolExecutionResult(
                         success=False,