feat(studio): app shell swap — mount EditorShell, retire the legacy engine

[ukimsanov]

What

the final swap (43 files): App mounts EditorShell; contexts, hotkeys, sidebar (AssetsTab→AssetCard, toolbar, audio row), useTimelineEditing and the store drop the legacy single-select API and trimmed callbacks; deletes the 7 files this orphans (StudioPreviewArea, NLELayout, useTimelineGroupEditing, timelineLayerDrag + suites, legacy hook test); .fallowrc.jsonc lands at final content, dropping every TEMP(studio-dnd) suppression — everything shipped unwired is now reachable.

Why

last step of the NLE integration; after this the tree is byte-identical to the previously-green integration checkpoint.

How

modified files to final content + gate-forced deletions + suppression cleanup. Tree parity with checkpoint 86dd2a32b verified.

Test plan

tsc --noEmit in studio, studio-server, core; bun run --filter @hyperframes/studio build; bunx vitest run (full suite); fallow audit clean with zero remaining TEMP entries; tree-diff vs 86dd2a32b empty.

---

Stack position 22/25 — studio NLE overhaul (CapCut-parity timeline + canvas). Graphite manages bases; merge from #2192 upward. Temporary TEMP(studio-dnd) fallow entries (unwired-component windows) are all removed by #2213 (app-shell swap), whose tree is byte-identical to the fully-verified integration branch.

Merge invariant: #2206→#2213 land as ONE ordered unit — no cherry-picks, no deploys between #2211–#2213 (review-fix foliation concentrates engine wiring at #2213; seam evidence in the #2205 thread).

[ukimsanov]

Warning

This pull request is not mergeable via GitHub because a downstack PR is open. Once all requirements are satisfied, merge this PR as a stack on Graphite.
Learn more

• feat(studio): assets/blocks panel behaviors + preview helpers #2216
• feat(studio): timeline visual refresh #2215
• feat(studio): clip thumbnail modules #2214
• feat(studio): app shell swap — mount EditorShell, retire the legacy engine #2213 👈 (View in Graphite)
• feat(studio): timeline glue swap — Timeline/TimelineCanvas onto the NLE engine #2212
• feat(studio): canvas glue swap — overlay, gestures, selection to final form #2211
• feat(studio): sidebar asset card (unwired) #2210
• feat(studio): NLE shell assembly (unwired) #2209
• feat(studio): canvas chrome components (unwired) #2208
• feat(studio): timeline interaction hooks and lanes component (unwired) #2207
• feat(studio): clip drag engine — preview and commit (unwired) #2206
• feat(studio): glue API coexistence layer for the NLE swap #2283
• feat(studio): NLE shell components — context provider, panes, overlays (unwired) #2282
• feat(studio): canvas nudge math + NLE shell components (pr12+pr13 recovery) #2278
• feat(studio): canvas context menu and z-order actions (unwired) #2281
• feat(studio): gesture characterization tests + canvas z-order menu (pr10+pr11 recovery) #2277
• feat(studio): asset click policy and canvas nudge gate #2280
• feat(studio): timeline collision and placement model #2279
• main

This stack of pull requests is managed by Graphite. Learn more about stacking.

[miga-heygen]

Reviewed as part of the 25-PR NLE overhaul stack. Full stack review on #2205 (the keystone). This is one of the critical swap PRs — reviewed with extra scrutiny. No blockers. — Miga

[miguel-heygen]

Blocker confirmed against current head 71f29f0: the Bug-2 regression describe block (8 tests) is nested inside the callback of the authored-none it(...) in gsapSoftReload.test.ts. Vitest silently ignores describes registered during a test, so the suite reports 24 passing while these 8 regression tests never register. Move the block to top level (after the authored-opacity describe closes), then rerun the targeted suite and request re-review.

[ukimsanov]

De-nest landed at the new head: the Bug-2 regression describe (8 tests) is hoisted to top level — targeted suite now registers and passes 32/32 (was 24 with 8 silently unregistered). Root cause was a bad conflict resolution during the restack onto main (the block got sealed inside the authored-none it callback); good catch on the silent-registration behavior. Requesting re-review of this head.

[miguel-heygen]

Re-audit at current head 6e37e12: Bug-2 describe block is now top-level (line 460, outside authored-opacity test); targeted registration issue resolved. Required CI including all regression shards, preview, perf, and format is green. Approving.

[miguel-heygen]

Re-reviewed current head and verified the addressed feedback and required behavior. Approval is for this exact head; Graphite mergeability may still be pending.