Parse tshark GSM field values with int(value, 0) instead of int(value)
to auto-detect hex 0x-prefixed output (e.g. 0x039e for TMSI/LAC/CID).
Without this, every tshark line with hex values fails to parse, causing
0 devices to be captured during monitoring.
Also add API Keys tab to Settings modal for configuring OpenCellID key
via the UI (in addition to env var), with status display and usage bar.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
- Cache lookup now requires non-NULL lat/lon — previously a row with
NULL coordinates counted as a cache hit, returning {lat: None, lon: None}
which the frontend silently ignored (tower in list but no map pin)
- API response handler validates lat/lon exist before caching, preventing
error responses (status 200 with error body) from poisoning the cache
- On geocoding worker start, delete any existing poisoned cache rows
- Geocoding worker now logs "API key not configured" vs "rate limit
reached" so the actual problem is visible in logs
- API error responses now log the response body for easier debugging
