chore(studio): remove all console.* calls from studio package (#1691)

* chore(studio): remove all console.* calls from studio package

* chore(studio): address review — remove dead stubs, restore consent notice

- Delete empty if-blocks left after console removal (snapTargetCollection,
  Player asset-poll, useTimelineSyncCallbacks 5s probe, useGestureRecording
  dev guard + now-unused isDevBuild) and the stale "surface in dev" comment.
- Drop the dangling no-console pragma + dead duplicate-id branch in sourcePatcher.
- Restore the one-time telemetry consent disclosure in showNoticeOnce (kept
  behind a pragma — it is a user-facing notice, not debug noise).
- Remove the missed timelineIcons console.warn while preserving the
  `tag || "div"` null-safety fallback.
- Route caption auto-save failures (a data-loss path) through telemetry
  instead of swallowing silently.
- Restore the accidentally-clobbered css-var-fonts output.mp4 fixture.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

---------

Co-authored-by: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

packages/studio/src/utils/optimisticUpdate.ts

@@ -11,8 +11,7 @@ export async function executeOptimistic<T>(options: OptimisticUpdateOptions<T>):
   const snapshot = options.apply();
   try {
     await options.persist();
-  } catch (error) {
+  } catch {
     options.rollback(snapshot);
-    console.warn("[optimistic] Mutation failed, rolled back:", error);
   }
 }