docs: synchronize recent audit findings

[davidkpiano]

Summary

• consolidate recent v6 action, actor, persistence, TypeScript, and migration documentation audits
• align custom clock and machine-version contracts with current core source

Validation

• source-contract assertions
• git diff --check
• docs paths are excluded by the repository Oxfmt configuration

[changeset-bot]

⚠️ No Changeset found

Latest commit: 5fba1ef

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