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/captions/hooks/useCaptionSync.ts

@@ -1,6 +1,7 @@
 import { useCallback, useRef } from "react";
 import { useCaptionStore } from "../store";
 import { useMountEffect } from "../../hooks/useMountEffect";
+import { trackEvent } from "../../telemetry/client";
 import type { CaptionStyle } from "../types";
 
 interface CaptionOverrideEntry {
@@ -78,7 +79,11 @@ export function useCaptionSync(projectId: string | null) {
       method: "PUT",
       headers: { "Content-Type": "text/plain" },
       body: JSON.stringify(overrides, null, 2),
-    }).catch((err) => console.warn("[captions] auto-save failed:", err));
+    }).catch((error: unknown) => {
+      // Caption auto-save is a data-loss path; surface failures via telemetry
+      // so a silently-dropped edit isn't invisible (no console in studio).
+      trackEvent("studio_caption_autosave_failed", { error: String(error) });
+    });
   }, []);
 
   // Auto-save on model changes with 800ms debounce