feat(skills): resolve --label and --assignee names in Linear create/update-issue

[zhang-liz]

What does this PR do?

Implements the in-source TODO at skills/productivity/linear/scripts/linear_api.py:232:

# TODO: label + assignee name->id lookup (omitted for v1 brevity)

create-issue already declared --label and --assignee argparse flags, but the handler dropped them on the floor — users had to fetch Linear UUIDs by hand. update-issue didn't expose the flags at all. After this PR both subcommands accept human-readable names and resolve them to UUIDs server-side, mirroring the existing _resolve_team_id (line 116) and the state-name lookup in cmd_update_status (lines 261–284).

Related Issue

No tracking issue — closes an in-source TODO.

Type of Change

• ✨ New feature (non-breaking change that adds functionality)

Changes Made

• skills/productivity/linear/scripts/linear_api.py
  • New _resolve_label_ids(team_id, names) — labels are team-scoped in Linear, so the query is team(id) { labels(first: 100) { nodes { id name } } }. Case-insensitive match. On miss: stderr + sys.exit(1) (matches the cmd_update_status precedent at line 273).
  • New _resolve_user_id(name_or_email) — matches against name, displayName, or email from the workspace users query. Case-insensitive. Tolerates null displayName/email.
  • cmd_create_issue: replaces the TODO; parses --label "Bug,P1" into a list, calls the resolvers, sets labelIds and assigneeId in the mutation input. Empty segments (",Bug,,") are ignored.
  • cmd_update_issue: adds the same fields. Because labels are team-scoped, when either flag is set we issue one extra issue(id) { team { id } } query first to recover the team id, then resolve. --title-only updates still take the existing one-query fast path.
  • Argparse: --label and --assignee added to the update-issue parser; help text updated on both subcommands.
  • Module docstring updated to document the new flag semantics.
• skills/productivity/linear/SKILL.md — short Quick Reference block under the "Python helper script" section showing the new flag usage. (The hand-written curl examples already documented labelIds/assigneeId in raw form, so no change there.)
• tests/skills/test_linear_skill.py — new. 17 stdlib-only tests using monkeypatch on linear_api.gql. Covers single/multi/case-insensitive label resolution, not-found exit semantics, null-field tolerance, both command wirings end-to-end, update-issue --title only (must skip the team lookup), empty-segment parsing, and update-issue with a non-existent issue identifier.

How to Test

# Fresh checkout of the branch, then:
pytest tests/skills/test_linear_skill.py -v -o addopts=""
# → 17 passed

# Lint and Windows-safety:
ruff check skills/productivity/linear/scripts/linear_api.py tests/skills/test_linear_skill.py
# → All checks passed!
python3 scripts/check-windows-footguns.py skills/productivity/linear/scripts/linear_api.py tests/skills/test_linear_skill.py
# → ✓ No Windows footguns found

# CLI smoke (no API call needed):
python3 skills/productivity/linear/scripts/linear_api.py create-issue --help
python3 skills/productivity/linear/scripts/linear_api.py update-issue --help
# Both render the new --label / --assignee flags with help text.

# End-to-end (requires LINEAR_API_KEY):
python3 skills/productivity/linear/scripts/linear_api.py create-issue \
  --team ENG --title "smoke" --label "Bug,P1" --assignee "Alice Smith"

Checklist

Code

• I've read the Contributing Guide
• My commit messages follow Conventional Commits
• I searched for existing PRs to make sure this isn't a duplicate
• My PR contains only changes related to this fix/feature
• I've run the new tests and they pass (pytest tests/skills/test_linear_skill.py -v -o addopts="" → 17 passed)
• I've added tests for my changes
• I've tested on my platform: macOS 15 (Darwin 25.3.0)

Documentation & Housekeeping

• I've updated relevant documentation (SKILL.md Quick Reference + module docstring)
• cli-config.yaml.example — N/A (no config keys added)
• CONTRIBUTING.md / AGENTS.md — N/A (no architecture change)
• Cross-platform impact considered: pure GraphQL + argparse, no process/file/term/Windows-sensitive calls. scripts/check-windows-footguns.py clean.

[alt-glitch]

Duplicate of #21143 — same feature (label and assignee name→ID resolution for Linear skill). Two prior PRs (#28628, #27213) were already closed as duplicates of #21143. Please consolidate there.

[zhang-liz]

Thanks for the catch — closing as duplicate of #21143. I searched the open bugs and existing PRs but missed the canonical feature ticket. Will consolidate via #21143 if it gets reopened for contributions; otherwise standing down. Apologies for the noise.