T-10: Fix get_geo_batch_lookup for proper injection with GeoCache instance

Instead of returning a bound method (geo_cache.lookup_batch), now inject
the GeoCache instance directly into routers and services. This provides
proper runtime isolation since T-04 made GeoCache a proper object.

Changes:
- Remove get_geo_batch_lookup() dependency provider
- Add GeoCacheDep type alias for injecting GeoCache instances
- Update all routers (bans, blocklist, dashboard, jails) to use GeoCacheDep
- Update ban_service, blocklist_service, jail_service to accept GeoCache
- Update service protocols to match new signatures
- Update docstrings to reference GeoCache methods instead of module functions

All callers now call geo_cache.lookup_batch(...) directly instead of
geo_batch_lookup(...), providing real dependency injection with proper
testing isolation.

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

backend/app/services/jail_service.py

@@ -52,7 +52,8 @@ if TYPE_CHECKING:
     import aiohttp
     import aiosqlite
 
-    from app.models.geo import GeoBatchLookup, GeoEnricher, GeoInfo
+    from app.models.geo import GeoEnricher, GeoInfo
+    from app.services.geo_cache import GeoCache
 
 log: structlog.stdlib.BoundLogger = structlog.get_logger()
 
@@ -749,7 +750,7 @@ async def get_jail_banned_ips(
     page: int = 1,
     page_size: int = 25,
     search: str | None = None,
-    geo_batch_lookup: GeoBatchLookup | None = None,
+    geo_cache: GeoCache | None = None,
     http_session: aiohttp.ClientSession | None = None,
     app_db: aiosqlite.Connection | None = None,
 ) -> JailBannedIpsResponse:
@@ -766,7 +767,7 @@ async def get_jail_banned_ips(
         page_size: Items per page; clamped to :data:`_MAX_PAGE_SIZE` (default 25).
         search: Optional case-insensitive substring filter applied to IP addresses.
         http_session: Optional shared :class:`aiohttp.ClientSession` for geo
-            enrichment via :func:`~app.services.geo_service.lookup_batch`.
+            enrichment via :meth:`GeoCache.lookup_batch`.
         app_db: Optional BanGUI application database for persistent geo cache.
 
     Returns:
@@ -817,10 +818,10 @@ async def get_jail_banned_ips(
     page_bans = all_bans[start : start + page_size]
 
     # Geo-enrich only the page slice.
-    if http_session is not None and page_bans and geo_batch_lookup is not None:
+    if http_session is not None and page_bans and geo_cache is not None:
         page_ips = [b.ip for b in page_bans]
         try:
-            geo_map = await geo_batch_lookup(page_ips, http_session, db=app_db)
+            geo_map = await geo_cache.lookup_batch(page_ips, http_session, db=app_db)
         except Exception:  # noqa: BLE001
             log.warning("jail_banned_ips_geo_failed", jail=jail_name)
             geo_map = {}