feat: add confirmed alias target change awareness - #39

Floating aliases can change target after a catalog refresh without making the transition visible. This adds native durable history, grouped TUI notices, and the latest transition in /model-aliases and inspection RPC.

• Establish a silent first baseline; record only confirmed final-catalog identities, including execution modelID changes.
• Preserve history through unresolved/inactive intervals; isolate directory/workspace and effective policy; keep only the latest transition.
• Acknowledge notices locally in each open TUI and persist them through native profile storage. Clients opened later under the same profile inherit acknowledgements; delivery remains best effort.
• Run Node 22/24 verification and packed-artifact smoke tests on OpenCode 2.0.16/2.0.24. Keep the required verify check as the aggregate gate.
• Clarify pinned references versus floating policies and add a working OMO-slim preset example.

Validation: 160 tests, lint, typecheck, build, and offline release checks pass. Node 22 verification passes. Both real hosts pass wire-model and zero-provider-call inspection tests; native storage preserves the same transition across two restarts. No paid API calls.

Closes #29
Closes #38

Advances the 0.3 trust/change-awareness milestone. Explain mode, configuration schema and remaining 1.0 boundary docs stay in 0.4; reload, minAge and priority remain optional backlog.