feat: git-like project versioning (v1)

Linear per-project history per notes/project-versioning.md: named
checkpoints (thumbnail via renderer.captureFrame) plus auto-checkpoints
on save (60s throttle, ring of 20, named never rotate). Restore writes a
safety checkpoint first, then swaps the document outside undo/redo.
Media assets referenced by any version are pinned against deletion.
Migration v31-v32 stamps the schema; the version store lives in its own
IDB database with an in-memory fallback for tests. Versions popover in
the editor header for jump/rename/delete. 12 new tests.

1 files changed, 3 insertions, 0 deletions

diff --git a/apps/web/src/core/index.ts b/apps/web/src/core/index.ts
index 0977666f..40352737 100644
--- a/apps/web/src/core/index.ts
+++ b/apps/web/src/core/index.ts
@@ -10,6 +10,7 @@ import { AudioManager } from "./managers/audio-manager";
 import { SelectionManager } from "./managers/selection-manager";
 import { ClipboardManager } from "./managers/clipboard-manager";
 import { DiagnosticsManager } from "./managers/diagnostics-manager";
+import { VersionsManager } from "@/versions";
 import { registerDefaultEffects } from "@/effects";
 import { registerDefaultMasks } from "@/masks";
 import { registerTranscriptionDiagnostics } from "@/transcription/diagnostics";
@@ -28,6 +29,7 @@ export class EditorCore {
 	public readonly selection: SelectionManager;
 	public readonly clipboard: ClipboardManager;
 	public readonly diagnostics: DiagnosticsManager;
+	public readonly versions: VersionsManager;
 
 	private constructor() {
 		registerDefaultEffects();
@@ -44,6 +46,7 @@ export class EditorCore {
 		this.selection = new SelectionManager(this);
 		this.clipboard = new ClipboardManager(this);
 		this.diagnostics = new DiagnosticsManager(this);
+		this.versions = new VersionsManager({ editor: this });
 		registerTranscriptionDiagnostics({ diagnostics: this.diagnostics });
 		this.playback.bindTimelineScope();
 		this.command.registerReactor(() => {