fix(node,client): query TMDB only once a language is chosen, in that languageHEADmain

TMDB fiches are fetched lazily, on browse, and the fetch used to run whatever
the moment it was first triggered — routinely before the operator had opened
settings and picked a language, so it queried in TMDB's English default. Then
the fiche was cached by tmdb_id alone, with no note of language and a 30-day
TTL, so switching to the intended language afterwards changed nothing: the
English fiche was served until it expired. The operator's only recourse was to
find and wipe the cache by hand (found live 2026-09-26: a whole library indexed
in English although "Français" had been chosen).

Two rules now, both there to make the first fetch the right language rather
than English-then-corrected, and to stop the doubled requests that eventually
get a node rate-limited:

- No language configured, no query. media_meta_req/season_meta_req answer
  confidence 0 and make no TMDB call while tmdb_language is unset; the fetch
  waits for the operator's choice, so the first (and only) query is in it.
  English is now a first-class choice (en-US), not the default of skipping the
  setting.
- Changing the language wipes the metadata cache (ops.set_tmdb_config), so the
  new language takes effect on an already-browsed library. The file->tmdb
  matches are language-independent and kept. The client refetches on the
  tmdb_config_ack that carries the new language, so the grid updates without a
  page reload.

docs/MESHBAY_DESIGN.md §9.7 states both rules; tests cover the gate and the
cache wipe, and two existing handler harnesses now declare a language.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

1 files changed, 16 insertions, 0 deletions

diff --git a/packages/meshbay-hub/src/meshbay_hub/static/video-app.js b/packages/meshbay-hub/src/meshbay_hub/static/video-app.js
index 124033e..4c9f90c 100644
--- a/packages/meshbay-hub/src/meshbay_hub/static/video-app.js
+++ b/packages/meshbay-hub/src/meshbay_hub/static/video-app.js
@@ -976,6 +976,22 @@ function VideoApp({
   useEffect(() => { setMode(loadViewMode()); }, [groupId]);
   useEffect(() => { setFilter(''); setTypeFilter('all'); }, [groupId]);
 
+  // When the operator changes the node's TMDB language, the node drops its
+  // metadata cache and refetches in the new language, and — until a language
+  // is set — answers nothing at all rather than querying in English (§9.7).
+  // Tell every mounted tile to redo its media_meta_req and drop the
+  // show-level meta already merged here, so the grid switches language (or
+  // fills in for the first time, right after the operator picks one) without
+  // a page reload. Skip the initial mount: the language is already right then,
+  // and bumping would restorm TMDB on every open of the Videos tab.
+  const tmdbLanguage = tmdbConfig ? (tmdbConfig.language || '') : '';
+  const firstLangRef = useRef(true);
+  useEffect(() => {
+    if (firstLangRef.current) { firstLangRef.current = false; return; }
+    setMetaByGroup({});
+    bumpMediaMetaGeneration();
+  }, [tmdbLanguage]);
+
   const setModeAndSave = (m) => { setMode(m); saveViewMode(m); };
 
   const videoEntries = availableEntries || entries;