fix(planning): stop the interview wording lint flagging release labels as question ids

[kyle-sexton]

No related issue: split out of #5191 after a repro pass on planning 0.46.0 (origin/main at 4d1d9d8).

Summary

Finding 14 of #5191, reported against planning 0.42.0: "V1" was flagged as a bare question id reference.

Fix

Narrow the pattern or add an exclusion list, and update the rule text.

Verification

Repro pass on origin/main, playwright-cli driving Chromium against a copy of plugins/planning/surface/, plus round.sh, watch.sh and curl. Verdict: reproduces.

ID_TOKEN = re.compile(r"\b[A-Z]+[0-9]+\b") at plugins/planning/surface/round.py:106; lint_questions warns on any such token that is not a question id (round.py:303-329). Live: round.sh add --title "Ship the V1 release on K8s?" ... printed warning: Z6 title names V1, which is not a question id in this file. "K8s" is not flagged. The same pattern is the documented convention (plugins/planning/skills/interview/context/surface.md:194), so the fix changes a stated rule as well as the regex.

Related

Refs #5191. #4653 tracks the commitment and export gaps behind findings 9, 17 and part of 18.