[Upd4ting]

Summary

The page index and the resource index each parsed the whole app into their own ts-morph project. They did it after every write, and again after every outside edit. The editor reads both right after each save: table usage, the page list and the table list. So each save paid two full parses.

 getSourceIndex()                  engine/source-index.ts
-  createModulesProject()          own parse
+  indexedProject()                engine/indexed-project.ts, shared
 getResourceIndex()                engine/resource-index.ts
-  createModulesProject()          own parse
+  indexedProject()

indexedProject() keeps the stamp check the two indexes had: a new parse once a file it read was written since, or after either index is invalidated. Each index rescans when the parse it read is replaced.

Evidence

Evidence level: benchmark of the engine operations, plus an end-to-end profile in the dashboard.

Workload: the repository playground in a fixture. An outside edit of the Board page is followed by what the editor reads after a save: table usage, ListPages and ListResources. Sides run interleaved, 5 runs each.

Workload	main	this PR
Rescan after an outside edit, 1 page	1063 ms (1042–1084)	584 ms (573–629)
Rescan after a write, 10 pages, 3 runs	1702 ms (1559–2025)	828 ms (782–1046)
Opening the editor, cold engine	2228 ms (2157–2289)	1700 ms (1644–1717)

In the dashboard, GET /api/builder/pages during the editor's open drops from about 550 ms to 15 ms. /resources has already parsed the shared project by then.

Cumulative impact: one parse less after every save and on every editor open, about 0.5 s of server CPU each time. The backend's event loop is blocked during a parse, so other requests wait too.

The engine specs (test:unit) pass: 523 passing.

Verification

• pnpm run checks passes. Main fails sync:check on a stale compat row in packages/dms-builder/README.md (interface-dms-builder 0.4.0, published 0.4.1), so a separate commit syncs it. It is the same line build(deps): move to @antelopejs/tooling-configs 0.5.0 #190 carries, byte for byte, so whichever of the two lands second has an empty or trivial conflict there.
• Verify harness on a stack of the three perf PRs: smoke, blocks (3), pages (3) and resources (4) journeys pass. Dashboard save, Save click to the server's answer, 15 saves per side: 2325 ms (2010–3792) on main, 630 ms (440–1102) with the three PRs.
• formal-page-save: the same output on main and on this branch. The only finding is the recorded F2 (Moving a page with an unsaved draft lets the next Save overwrite an outside change without the stale banner #163), which none of these lines touch. The gate flags the covered code's emit as changed.

Merge Danger

Door: two-way.

Blast Radius: page and resource listings.

Invalidating one index now also rescans the other: RefreshSourceIndex reads resources again too. Neither scanner edits the project, and every write opens its nodes from the writable project.