Separate Autopilot execution continuity assurance

[drafael]

Summary

• add versioned per-mode execution assurance for ownership, continuity, terminality, and admission while deriving compatible defaults for old protocol-v1 manifests and journals
• persist admission intent before launch and exact adapter/backend/subject identity after launch
• remove reattach() ?? launch() and require exact identity for process-supervised reattachment
• classify lost admission, terminal observation, adapter discovery, and cooperative continuity as nonterminal EXECUTION_STATE_UNKNOWN
• preserve pause cancellation across restart and permit stop to retry a failed or unaccepted cancellation
• surface selected assurance and admitted subject in reports

Validation

• npm test — 185 tests, 177 passed, 8 platform skips, 0 failures
• npm run typecheck
• npm run lint
• npm run format:check
• modified Markdown local-link check
• git diff --check
• generated dist/ rebuilt from source
• independent review found four P1/P2 race/continuity issues; all corrected and the second review found no issues

Compatibility

restartReattachment remains readable as the protocol-v1 compatibility field. New attempts persist the selected versioned assurance, while old journals continue to derive their existing session-scoped or supervised behavior.