docs: scope Linear reporting to this project and pin Closes-line discipline

[ichoosetoaccept]

Summary

Two repo-local rules in CLAUDE.md:

1. Linear queries from this repo filter to the copier-uv-bleeding project, not the whole DOT team.
2. Re-check a PR body's Closes/Refs lines whenever a commit is appended to an already-open PR.

Why

Rule 1 is noise reduction. The DOT team also tracks a macOS app and career/website work. An unfiltered list_issues returns sixty rows to surface the eight that concern this template.

Rule 2 is the DOT-629 post-mortem. Linear's GitHub integration closes on a bare Closes DOT-NNN and deliberately does not close on Refs. #345 carried exactly one tracker line — Refs DOT-620 — written when the PR held three commits. The testmon fix landed as a fourth commit afterwards and named DOT-629 nowhere: not in its own message, not in the body. It shipped in 0.41.13 and the issue stayed in Backlog until someone audited by hand.

The failure mode is specific to stacked PRs, where the body is written once and the commits keep arriving.

Test plan

Documentation only — no code paths touched. prek hooks (markdownlint, typos, lychee) pass.

Greptile Summary

Adds repository-local Linear guidance for contributors working on this Copier template. The new instructions scope issue searches to the copier-uv-bleeding project, distinguish closing references from non-closing references, and remind authors to update issue references when appending work to an open PR.

The updated guidance was checked against the previous and current versions of CLAUDE.md: the new version contains the required project filter and clearly defines the separate Closes DOT-NNN and Refs DOT-NNN behaviors. No defects were found.

Confidence Score: 5/5

T-Rex Logs

What T-Rex did

• Ran the review-authored checker against the parent CLAUDE.md and the updated CLAUDE.md; the parent failed due to missing Linear guidance, while the updated version passed after identifying the copier-uv-bleeding project filter and distinct Closes DOT-NNN and Refs DOT-NNN conventions.
• Reviewed the executable script named linear-guidance-check.py to confirm it extracts the Issue Tracking contract and asserts the required project filter and Closes/Refs semantics.
• Compared the before and after logs to verify the pre-capture failure turned into a passing post-capture state.
• Mapped the supporting artifacts to verify the above conclusions, including the checker results and the linear guidance script and logs.

_{Ran code and verified through T-Rex}

_{Reviews (1): Last reviewed commit: "docs: scope Linear reporting to this pro..." | Re-trigger Greptile}

[linear-code]

DOT-620

[ichoosetoaccept]

This change is part of the following stack:

• docs: scope Linear reporting to this project and pin Closes-line discipline #346 ◀
  • fix(template): stop chmodding scripts the template does not own #347
    • test: tolerate copier's temp-clone cleanup race on a dirty tree #348

_{Change managed by git-spice.}