feat(workbench): route editor state on effect-atom (#105 phase 2)

[ScriptedAlchemy]

Summary

Phase 2 of the #105 effect-atom migration (phase 1: #250). The routes-page route-input editor state — previously seven coordinated useState/derivation clusters per editor (draft, raw JSON, errors, rawError, attempted, arguments, argv) — moves onto an Atom.family keyed by manifest digest + compiled route id, in a new dedicated browser-state module per the docs/effect-conventions.md "Workbench browser state" convention.

• packages/workbench/src/routes/route-editor-atoms.ts: writable Atom.family keyed digest\u0000routeId, initial value undefined (uninitialized sentinel). No effects, no streams (stream-backed derived atoms remain banned until the post-rc.112 re-pin), no Atom/AsyncResult in any public export.
• packages/workbench/src/routes/routes-model.ts: stays pure — adds RouteEditorState + pure transitions (initialRouteEditorState, setRouteEditorDraftValue, setRouteEditorRaw, validateRouteEditor) that derive from the untouched validateRouteInput / validateRawRouteInput / cliCommandInvocation projections.
• packages/workbench/src/routes/routes-page.tsx: RouteInputEditor consumes the atom via useAtom with functional updaters; markup unchanged; RoutesPage public props unchanged.

The undefined sentinel is what keeps provider-less static SSR rendering byte-identical initial markup (useAtomValue's getServerSnapshot returns the initial atom value), so the existing contract tests pass unmodified.

Preserved behavior contracts (#222/#224 fixes)

routes-model.test.ts, routes-page.test.ts, and examples-real.e2e.test.ts are untouched and green. Pinned explicitly by new unit tests: optional-boolean omitted/true/false three-state, stale-prefill fail-closed paths untouched (mcpToolPrefillFor gating on validated arguments preserved), variadic/repeated-option argv + usage projection, attempted-gated re-validation, and the raw-path asymmetry (raw edits after Validate update rawError/arguments but never argv).

Disposal regression (phase-1 pattern)

route-editor-atoms-disposal.test.ts (integration pool): rsbuild browser fixture mounting the real RoutesPage under a bare RegistryProvider; 5 mount → type → validate → unmount → remount cycles assert fresh initial state each remount, plus an A→B→A digest-switch cycle; zero page errors.

Verification (local, after rebasing over #259)

• lint: 0 errors / 0 warnings (915 files)
• typecheck: this diff is clean; pnpm typecheck currently fails on pristine origin/main (TS7016 in classify-docs-only.test.ts from ci: extract docs-only classifier tests and retry stale-diagnostic e2e flakes #259) — pre-existing, reproduced on a clean main worktree
• scoped units (routes-model + routes-page + new routes-editor-state): 40/40
• full integration + workbench browser e2e: 61 files / 629 tests — 625 passed, 3 skipped, 1 failed: public-api.test.ts :: keeps bundled config extension types in emitted root declarations, pre-existing (fails identically on a pristine origin/main worktree; unrelated to workbench)
• new disposal regression: 1/1 pass

Bundle delta (workbench production build)

	raw	gzip
before (main)	2770.4 kB	595.3 kB
after	2770.7 kB	594.9 kB
delta	+0.3 kB (+0.01%)	−0.4 kB (−0.07%)

Near-zero as predicted — the effect core + atom runtime entered the shared chunk in phase 1.

Patch changeset included (agent-bundle ships the Workbench dist).

[changeset-bot]

🦋 Changeset detected

Latest commit: 84b2ca7

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 1 package

Name	Type
agent-bundle	Patch

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[chatgpt-codex-connector]

Codex Review Summary

This comment shows the latest Codex review activity on this pull request.

Review	Status	Commit	Review trigger
📝 Code Review	✅ Completed 2026-09-02T02:53:33.267063Z	84b2ca7	PR opened

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