EPIC: Standalone OS and Rust-engine programme

Programme: #1

Own the dedicated desktop session/distribution path, alternative Rust engine track and separately staffed Rust-kernel research/delivery programme.

## Child issues
- [ ] #105 OS-01 — Dedicated session and immutable distribution
- [ ] #106 OS-02 — Servo and alternative-engine compatibility track
- [ ] #107 OS-03 — Rust-kernel architecture and reuse assessment
- [ ] #108 OS-04 — Virtualized Rust-kernel substrate
- [ ] #109 OS-05 — Desktop, speech and inference OS ports
- [ ] #110 OS-06 — Compatibility, hardware and supported Rust OS release

## Cross-cutting gates
User-space runtime remains portable, inference stays unprivileged, Chromium fallback stays truthful until alternatives pass compatibility, kernel work has explicit hardware/ABI/driver/browser/inference plans, and OS failure recovery works with inference disabled.

Start by reviewing child issues #105–#110 to identify a bounded work item, then read the cross-cutting gates in this issue. Done means the selected OS or Rust-engine work satisfies its child-issue scope while preserving portability, unprivileged inference, truthful fallback, explicit kernel plans, and recovery with inference disabled.

Written by the indexing model from the issue text.