Goal

Track the remaining runtime-boundary hardening work that was intentionally left after the narrower fixes in #412 and #413.

This is a tracker issue, not a directly implementable PR. It should stay open only while it helps keep the child tasks visible. Each implementation must happen through a smaller child issue or PR with its own scope and verification.

Scope

In scope for this tracker:

• Keep the runtime-boundary follow-up map current.
• Split broad architecture work into review-sized child issues before implementation.
• Link child PRs or issues back here when they land.
• Close this tracker only when the remaining useful follow-ups are either completed, superseded, or moved into clearer standalone issues.

Tracked boundary areas:

1. Navigation ownership

   • Core route-ownership hardening for openProject(projectRoot), openSession(directory, sessionID), and newSession(directory) landed in [Task] Harden interaction locks and session route ownership #413.
   • Keep explicit session URLs as the source of truth for session pages.
   • Any remaining work here should be a narrower follow-up, not a reopening of the original broad route-ownership task.

2. Interaction locks

   • The first shared hardening pass for temporary interaction locks landed in [Task] Harden interaction locks and session route ownership #413.
   • Any remaining work here should focus on narrower owner/release/timeout follow-ups rather than re-bundling the original broad interaction-lock audit.

3. Desktop runtime manifest

   • Define the packaged native/runtime resources the embedded desktop runtime requires.
   • Keep watcher/native dependency packaging from being rediscovered by accident.
   • Make packaging config and packaging tests read from one manifest-like source where practical.

4. Diagnostics

   • Renderer diagnostics precedent landed in [Task] Add renderer diagnostics for session jump and flicker observability #389 for session jump and flicker observability.
   • Remaining work here should stay focused on runtime-boundary diagnostics that are still missing, especially route-action and interaction-lock-specific signals where needed.
   • Prefer data that helps debug packaged-app failures and agent-led triage.

Out of scope

• Do not implement all four areas in one PR.
• Do not rewrite the router or change route shapes from this tracker alone.
• Do not replace Solid, Electron, the sidecar, or the SDK layer.
• Do not include a normalized entity-store rewrite, timeline virtualization, or broad prefetch scheduler work.
• Do not create local-only design docs unless they are tied to an implementation PR.

Relevant files or context

Related context:

• fix: package native watcher in desktop builds #412 fixed urgent packaged native watcher coverage and an immediate resize clickability path.
• [Task] Harden interaction locks and session route ownership #413 hardened two concrete P1 boundaries: temporary interaction locks and explicit session route ownership.
• [Task] Add renderer diagnostics for session jump and flicker observability #389 added renderer diagnostics for session jump and flicker observability, which covers part of the diagnostics direction tracked here but does not by itself close the broader runtime-boundary map.

Likely areas:

• packages/app/src/pages/layout.tsx
• packages/app/src/pages/layout/helpers.ts
• packages/app/src/pages/session/helpers.ts
• packages/ui/src/components/resize-handle.tsx
• packages/desktop-electron/electron-builder.config.ts
• packages/desktop-electron/scripts/prepare-embedded-server.ts
• packages/app/e2e/sidebar/
• packages/app/e2e/commands/

Verification

For each child PR or child issue:

• Add focused unit tests for the boundary contract being changed.
• Add or update the smallest relevant user-path E2E coverage, especially delayed route stability and post-interaction clickability.
• Run targeted app/ui typechecks and affected Playwright specs.
• Confirm there are no route-shape, product-copy, or broad layout changes unless that child issue explicitly asks for them.

Priority

P2.

This is important architecture hardening, but concrete user-visible or release-blocking regressions should stay in narrower P1 issues. Do not raise this tracker just because one child task becomes urgent; raise that child issue instead.

Execution mode

Agent should propose a small child issue or PR plan before editing. Keep each implementation independently reviewable and reversible.