fix(cctv): back off the Taiwan catalog when unreachable; review fixes

- taiwan.js: a failed download serves the last good table (up to 24 h)
  and is not retried for an hour. The table host does not answer from
  some networks outside Taiwan, and each attempt held the shared catalog
  refresh for the ~10 s connect timeout.
- Own server/providers/cctv/taiwan.js in package-boundaries.json
  (check:boundaries failed).
- Decode numeric character references; name falls back to the CCTVID
  when a row has no road details.
- Credit names the dataset and links the OGDL Taiwan licence.
- Document CCTV_TAIWAN_URL; list Taiwan in the CURRENT-STATE source table.
- Tests: isolate catalog env, reset loader state, cover the byte cap,
  failed fetch, backoff, last-good fallback, cap clamping, redirect with
  a valid body, name fallback, numeric entities and UUID camera ids.

Co-Authored-By: Claude Opus 5.5 <[email protected]>

scripts/package-boundaries.json

@@ -191,6 +191,7 @@
       "server/providers/cctv/groundHeights.js",
       "server/providers/cctv/catalog.js",
       "server/providers/cctv/lithuania.js",
+      "server/providers/cctv/taiwan.js",
       "server/providers/cctv/constants.js",
       "server/providers/cctv/media.js",
       "server/providers/cctv/normalize.js",