fix(daemon): preserve brief delivery state across task switches

[open-design-crew]

Fixes #6777

Why

Use case: QA reproduced a confirmed and delivered Open Design brief returning to its initial state after switching away from a Codex task and back.

Pain: Showing Confirm requirements again implies the brief was not sent and lets the same confirmed payload be published repeatedly after each card remount.

What users will see

A delivered requirements brief remains locked and displays the sent state after switching Codex tasks. If publication failed after confirmation, the remounted card offers only Continue sending and does not confirm the brief again.

Surface area

• UI — new page / dialog / panel / menu item / setting / empty state in apps/web or apps/desktop (including Electron menu bar)
• Keyboard shortcut — new or changed
• CLI / env var — new od subcommand or flag, new tools-dev / tools-pack flag, or new OD_* env var
• API / contract — new /api/* endpoint, new SSE event, or changed shape in packages/contracts
• Extension point — new entry under skills/, design-systems/, design-templates/, or craft/, or change to the skills protocol
• i18n keys — added new translation keys (see TRANSLATIONS.md for the locale workflow)
• New top-level dependency — adding any new entry to the root package.json (dependencies or devDependencies); workspace-package package.json files are out of scope. Include a paragraph on what we get vs. what bytes we ship (see CONTRIBUTING.md → Code style)
• Default behavior change — changes what existing users experience without opting in (default model, default setting, file/SQLite schema, auto-network on startup, auto-install)
• None — internal refactor, docs, tests, or translation update only

Screenshots

Not applicable.

Bug fix verification

• Test path that reproduces the bug: apps/daemon/tests/mcp-brief-app.test.ts
• Red on main: yes
• Green on this branch: yes
• Explanation: The focused remount tests failed before the production change: a delivered card restored with an empty status and visible confirmation action, while a publication failure lost its Continue sending action. Both pass on this branch.

Validation

• Focused remount red spec on the pre-fix source: 2 failed
• Focused remount regression after the fix: 2 passed
• pnpm exec vitest run -c vitest.config.ts tests/mcp-brief-app.test.ts: 19 passed
• pnpm --filter @open-design/daemon test: 645 files passed, 8232 tests passed
• pnpm --filter @open-design/daemon typecheck
• pnpm --filter @open-design/daemon build
• pnpm guard
• pnpm typecheck
• git diff --check