Refine timezone="auto" so it ALWAYS resolves (drop the "host" sentinel):
- ""/"auto" resolve from the proxy egress when a proxy is set, else from the
host own public IP (direct lookup); an explicit zone is the only opt-out.
- on failure: with a proxy raise; without a proxy fall back to the host TZ.
GeoIP DB now auto-updates against daijro/geoip-all-in-one weekly rebuild:
cache the latest, re-check after GEOIP_REFRESH_DAYS (7), prune old tags,
reuse a stale cache offline; GEOIP_MMDB_VERSION is only the cold fallback.
tests: test_geo.py (37) + test_geoip_update.py; full unit suite 429 green
plus 8 live combinations (proxy / no-proxy / explicit / failing / freshness).
A proxy in a different country paired with the host timezone is the
classic timezone_mismatch signal, so a session with a proxy and no
explicit timezone now resolves the zone automatically.
- discover the egress IP through the proxy (SOCKS via requests[socks]),
map it to an IANA zone with an offline mmdb (daijro/geoip-all-in-one,
downloaded + cached like the Firefox binary; GPL so not vendored)
- precedence: explicit zone wins; ""+proxy and "auto"+proxy resolve;
""/"auto" without a proxy stay host; "host"/"local" force host TZ
- fail-early when a proxy is set but the zone cannot be resolved, never
a silent host-TZ fallback
- deps: requests[socks], maxminddb, tzdata (zoneinfo ships no DB on Windows)
- resolve_session_timezone / ensure_geoip_mmdb exported for integrations
