fix: tour -- also block Save video, a dormant landmine round 2 flagged

Round 2's review of the syncFromPreview fix came back clean but flagged an
adjacent, currently-dormant gap while tracing the same pattern: the "Save
video" button (Store.saveClipToMediaBin -> API.importClipToMediaBin) is
neither in patchStore()'s block list nor patchApi()'s mock list, and it
already renders during the tour (tour-s2 satisfies
clipSaveableToMediaBin()). It's harmless today only because
importClipToMediaBin is itself a stub ("no render/stitch stage yet") --
the moment that stage lands, this becomes a real, unblocked PUT during the
tour with nothing prompting anyone to notice. Closing it now with the same
established pattern rather than leaving it for a future regression.

Verified live: Store.saveClipToMediaBin now returns the block toast
directly, and a full tour run completes with zero thrown errors.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

app/legacy/tour.js

@@ -344,7 +344,7 @@
       "generate", "generateMontage", "generateSelected", "renderFinal", "exportSelected",
       "saveSelectedToMediaBin", "commit", "newProject", "loadProject", "deleteProject",
       "importProject", "downloadProject", "uploadMedia", "deleteMedia", "deleteMediaMany",
-      "interrupt", "resetStudioSession", "syncFromPreview",
+      "interrupt", "resetStudioSession", "syncFromPreview", "saveClipToMediaBin",
     ];
     const labels = {
       generate: "Generate",
@@ -369,6 +369,12 @@
       // call) without going through anything else already on this list, so
       // it needs its own block rather than relying on "commit" to cover it.
       syncFromPreview: "Sync scenes from preview",
+      // Not reachable via a real network call today -- API.importClipToMediaBin
+      // is itself a stub ("no render/stitch stage yet") -- but the button
+      // already renders during the tour (tour-s2 satisfies
+      // clipSaveableToMediaBin()), so this needs blocking now rather than
+      // whenever that stage lands and the stub silently becomes a real PUT.
+      saveClipToMediaBin: "Save video",
     };
     blocked.forEach((name) => {
       if (typeof Store[name] !== "function") return;