OR-255: Meaningful URLs and workspace restoration

[sox8502]

Implements OR-255: meaningful project/task/settings URLs and workspace restoration from the current runtime’s SQLite database. TanStack Router owns navigation; saved tab metadata restores files, experiments, plans, subagents, and layout without restarting compile/sync work.

• Four independent Codex reviewers: no blockers after fixing review findings
• 109 UI tests, route generation/typecheck, localization/style checks, and dev-slot tests
• Rust fmt, clippy, locked builds and 733 tests (0 failures; 2 release-only tests ignored)
• Debug and release builds report the development telemetry channel
• Regenerated committed ui/dist
• Browser checks: refresh/restart, task switching and Back/Forward, settings resume, malformed pane cleanup, retained hidden tabs, source mode, passive LaTeX, dirty-navigation cancellation, file refocus, malformed task IDs, live projects-home updates, deep-link close fallback, and unavailable wrong-branch links
• User acceptance across archived tasks, plans/subagents, and experiment/run deep links
• Live SSH reconnect, onboarding, and Overleaf integration smoke tests

Unsaved file contents, composer drafts, generated PDFs, and cross-window synchronization remain outside this change.