Merge upstream/main into pr/google-street-view

Conflicts with upstream's Street Level provider composition and share-state
codec, resolved:

- Street View's switch moves from its own share option (`g`) to upstream's
  provider-switch field (`r`, e.g. `0.r.google-1`); a link without it keeps
  Street View off. Docs and the browser gate follow.
- createApplicationStreetLevel keeps upstream's injectable provider list;
  its default, once the application supplies its Street Level source, is
  Mapillary plus Google Street View. Without that source there are none, as
  upstream intends.
- The coverage hint keeps upstream's empty-composition message and joins
  every switched-on provider's hint otherwise.
- CHANGELOG, README and SECURITY keep both sides' entries.

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

CHANGELOG.md

@@ -1,5 +1,37 @@
 # Changelog
 
+- Treat explicitly current, complete empty vessel coverage as a successful update,
+  clearing obsolete contacts while retaining stale or incomplete snapshots.
+
+- Custom Street Level provider switches survive share links and stored state
+  using URL-safe stable provider IDs and a shared boolean-switch codec; existing
+  Mapillary links keep their meaning. Explicit provider toggles reach durable
+  state without adopting unrelated live switch changes.
+
+- Directions and Recent Imagery accept replaceable acquisition sources, including
+  route transport, imagery catalog, thumbnails, tile templates and attribution.
+  Explicitly removing either source leaves its layer unavailable; standalone
+  defaults preserve the existing providers.
+
+- Catalog source availability no longer modifies layer objects; unavailable
+  tooltips use layer display names.
+
+- Street Level with no providers uses the shared unavailable state and refuses
+  activation before initialization, while keeping its layer identity visible.
+
+- Application source configuration accepts replacements and explicit removal.
+  Missing catalog feeds leave their layers unavailable without blocking startup
+  or making fallback requests; malformed supplied feeds remain configuration errors.
+
+- Street Level providers are optional in application composition. Omitting a
+  Mapillary source no longer prevents startup; callers can inject a different
+  provider list or an empty list without changing layer identities or share links.
+
+- Vector tile sources take their allowed tile origin from the configured
+  `tileJsonUrl`, so repointing only that URL at a mirror loads tiles from the
+  mirror or fails visibly instead of silently using OpenFreeMap. Thanks to
+  [daikaginza](https://github.com/daikaginza) (#935).
+
 - MCP setup examples use the app's default port, `4173`. Thanks to
   [Huanyi Xie](https://github.com/xiehuanyi) (#934) and
   [shirunjies8-png](https://github.com/shirunjies8-png) (#959) for the same fix.
@@ -69,7 +101,20 @@
   Maps JavaScript API) and click a street, or press OPEN STREET VIEW, to
   open Google's own panorama in
   the panel, with its arrows, the address and month in the caption, a link
-  to Google Maps and FOLLOW. Share links carry it as `g`.
+  to Google Maps and FOLLOW. Share links carry it in the provider switches
+  (`r.google-1`).
+
+- Add an experimental ChatGPT/Codex OAuth option for cloud voice in Provider
+  Settings. API-key voice remains the default. Local sign-in can start from
+  the auth button and reports completion, failure, timeout, or expired
+  credentials. OAuth credentials stay on the server; local routes require
+  loopback access and same-site requests. OAuth sessions retain usage data
+  and show unknown cost; caption transcriptions are counted rather than
+  priced into the API-key cap. The auth button keeps keyboard focus after a
+  mode change, and pending sign-in does not discard text in the key fields.
+  Thanks to [Shayan Khan](https://github.com/devv-shayan) for #621 and
+  [TheSmokeDev](https://github.com/TheSmokeDev) for the credential handling
+  from #653.
 
 - Stdio servers from one install share a panel key so a page read from one
   process can make requests through another. Concurrent malformed-key repairs