fix(cctv): make the Lithuania pack opt-in until its licence is confirmed

The camera endpoints are the eismoinfo.lt website backend, which the Via
Lietuva open-data statement does not list, so the pack now follows the NYC
opt-in pattern (CCTV_LITHUANIA_ENABLED=1) and the docs say why. A failed
catalog request now aborts its sibling instead of leaving it open until the
timeout, and a redirect is logged as not followed.

.env.example

@@ -226,7 +226,7 @@ AISSTREAM_API_KEY=
 # CCTV_NYC_ENABLED=                                    # off by default; set 1 only if you hold a NYC DOT data-sharing agreement ([email protected]) for the camera feed
 # CCTV_NYC_MAX_SOURCES=250                             # cap cameras loaded from the NYC TMC catalog (nearest borough cores first)
 # CCTV_NYC_CAMERAS_URL=                                # override the NYC TMC catalog URL
-# CCTV_LITHUANIA_ENABLED=1                             # set 0 to disable Via Lietuva / Eismoinfo road cameras
+# CCTV_LITHUANIA_ENABLED=                              # off by default; set 1 to load Via Lietuva / Eismoinfo road cameras (photo licence unconfirmed; see DATA_SOURCES.md)
 # CCTV_LITHUANIA_MAX_SOURCES=400                       # cap Lithuanian cameras; no API key required
 # CCTV_MAX_SOURCES=4000                                # catalog-wide ceiling, shared round-robin across packs
 # CCTV_PREFER_AUSTIN=1                                 # prioritize Austin cameras in the registry