docs(D5.1c): revisit trigger + tracking issue for the deferred exclusivity axis

[PhysShell]

What & why

Records the decision to keep declining transitive borrow_mut propagation through MOS wrapper summaries (the question raised on #113 / Codex P2).

The design was already captured as D5.1c — transitive borrow-kind propagation (deferred) in docs/notes/d5-ownership-transfer.md, so this does not duplicate it. It adds the two things that entry lacked:

1. an explicit revisit trigger — land the borrow-kind axis alongside the first interprocedural exclusivity consumer (an OWN006/011/012/013-class conflict checked across the call boundary; today exclusivity is enforced only intraprocedurally and at the direct $borrow_mut call), and
2. the cheap-to-reverse rationale — the skeleton already preserves the forward edges (PathAction(kind="forward", …)), so the future work is additive (leaf borrow-kind + a join), not a solver rebuild,

plus a link to the live tracker #122.

Net of the decision: decline now, defer the fix — precision-first, no observable cost because the exclusivity summary axis has no interprocedural reader yet.

Docs-only; no code change.

🤖 Generated with Claude Code

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Generated by Claude Code

Summary by CodeRabbit

• Documentation
  • Expanded the ownership-transfer notes with clearer guidance on when the deferred exclusivity axis will become actionable.
  • Clarified that the feature is currently unused and that future work can be added incrementally.
  • Added a live tracker reference for follow-up progress.

[coderabbitai]

No actionable comments were generated in the recent review. 🎉

ℹ️ Recent review info

⚙️ Run configuration

Configuration used: Path: .coderabbit.yaml

Review profile: CHILL

Plan: Pro Plus

Run ID: f2fa4d4d-8aba-4271-b8e4-ec41c985eb1a

📥 Commits

Reviewing files that changed from the base of the PR and between c1dfb2e and 922dd7e.

📒 Files selected for processing (1)

• docs/notes/d5-ownership-transfer.md

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📝 Walkthrough

Walkthrough

This documentation update adds a revisit trigger for the D5.1c borrow-kind axis, states it currently has no consumer, and records tracker #122.

Changes

D5.1c deferred axis note

Layer / File(s)	Summary
Deferred axis criteria docs/notes/d5-ownership-transfer.md	The note adds the cross-call-boundary exclusivity conflict-checking trigger, states the axis has no current consumer, and records the forward plan as additive with tracker #122.

Estimated code review effort

🎯 1 (Trivial) | ⏱️ ~2 minutes

Poem

A bunny nibbled through the notes so neat,
Hop-hop, a trigger landed crisp and sweet.
No consumer now, yet paths stay яс?
Oops—just fluff: the plan stays bright and clear,
Tracker #122 makes the burrow cheer. 🐰

🚥 Pre-merge checks | ✅ 4

✅ Passed checks (4 passed)

Check name	Status	Explanation
Description Check	✅ Passed	Check skipped - CodeRabbit’s high-level summary is enabled.
Title check	✅ Passed	The title clearly matches the documentation update and highlights the new revisit trigger and tracking issue for the deferred exclusivity axis.
Linked Issues check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check	✅ Passed	Check skipped because no linked issues were found for this pull request.

✨ Finishing Touches

🧪 Generate unit tests (beta)

• Create PR with unit tests
• Commit unit tests in branch claude/p005-exclusivity-defer

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