Add project versioning & publish flow (#130)

* Add project versioning & publish flow

Introduce project model versioning and publishing support.

- DB: add published_model_version column to projects (migration + schema + types).
- Models: add version status types and helpers, implement getProjectVersionStatus, enhanced getProjectModel to load draft/published/legacy fallbacks, saveProjectModel now manages draft creation/updating and avoids no-op saves, saveProjectVersion to lock/save/publish versions and create next draft, publishProjectModel to republish specific saved versions. Includes scene-graph equality checks and authenticated project ownership checks.
- UI: AppSidebar shows publish/draft status, polling refresh, and Save / Save & publish / Publish actions that flush the editor scene before version operations. Hook update: load scene from result.data.model.scene_graph.
- Public project loader: prefer published version with legacy fallbacks.

This enables safe draft editing, explicit saves, publishing, and keeps autosave working across version locks.

* Add project versioning UI, APIs & preview mode

Introduce full version management support: UI, backend actions, and editor integration.

- UI: Add a Versions popover to the app sidebar with search, relative timestamps, preview, restore and publish controls; disable version actions while previewing and show proper labels/states. Imported new icons, popover and tooltip primitives and added formatRelativeTime helper.
- Actions: Add ProjectVersionListItem type and APIs getProjectVersionList and getProjectVersionByNumber to list and fetch saved (non-draft) versions.
- Hooks: Extract applySceneGraphToEditor and sync editor selection logic; ensure scene loading applies selection and supports preview mode (which suppresses autosave).
- Store: Add isVersionPreviewMode to project store with setter and isSceneLoading flag usage to prevent autosave while previewing.
- Misc: Wire up version list loading, previewing, restoring and publishing flows, and refresh version status/list after actions.

These changes enable browsing historical project versions, previewing them without triggering autosaves, and restoring or publishing selected versions.

* Improve version preview, restore flow & draft handling

- Add scene graph snapshot to preserve unsaved work during preview
- Include draft versions and metadata in version list
- Add getProjectVersionById for direct ID-based lookups
- Add autosave status to project store
- Refactor sidebar version UI (remove search, use save icon)

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

---------

Co-authored-by: Claude Opus 4.6 <noreply@anthropic.com>

packages/db/src/schema/projects/projects.ts

@@ -18,6 +18,7 @@ export const projects = pgTable(
       .references(() => users.id, { onDelete: 'set null' }),
     detailsJson: t.jsonb('details_json'),
     metadata: t.jsonb('metadata'),
+    publishedModelVersion: t.integer('published_model_version'),
     // Community features
     isPrivate: t.boolean('is_private').notNull().default(true),
     isEmpty: t.boolean('is_empty').notNull().default(true),