feat: add source-backed work view

[dlxeva]

Summary

• add an opt-in source-backed work view derived from one declared Markdown source block
• track block-level SHA freshness so unrelated edits stay fresh and in-block edits require recheck
• suppress stale current actions in resume and manifest context
• surface unbuilt, invalid, and stale work views through flg doctor --strict
• keep project-specific table semantics in optional project adapters

Verification

• 255 tests passed
• Python compileall passed with an isolated bytecode cache
• git diff --check passed
• large-table shadow fixture: an out-of-block edit stayed fresh and an in-block edit became stale / needs_recheck
• generic Markdown fixture: current action, blockers, constraints, locator, and SHA compiled; a changed action was suppressed until rebuild

Boundary

• no second writable ledger
• no Agent Memory integration
• no proprietary task IDs, owner identities, local project names, or private source content in core
• Windows-neutral output; no sed dependency

[chatgpt-codex-connector]

Codex Review Summary

This comment shows the latest Codex review activity on this pull request.

Review	Status	Commit	Review trigger
📝 Code Review	✅ Completed 2026-09-10T20:09:31.605966Z	8d4a2eb	Draft marked ready

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