feat(skills): add pre-filing version check to swamp-issue bug workflow

[stack72]

Summary

• Converts the swamp-issue skill's bug report workflow from a linear step list to a state machine (gather_details → version_check → submit → verify) matching the swamp-getting-started pattern
• Adds a version_check state that checks if the user is on an outdated binary, fetches the latest source via swamp source fetch, and has the agent re-read diagnosed files to determine if the bug was already fixed
• Three outcomes: bug_fixed (tell user to update), bug_present (proceed to file), inconclusive (proceed to file) — never blocks filing
• Feature/security workflows remain linear (no version check)
• Adds references/version_check.md with the detailed procedure

Closes swamp-club#321.

Test plan

• Invoke swamp-issue skill to file a bug against swamp — verify the agent runs the version check state before submitting
• Verify swamp update --check --json output is parsed correctly
• Verify swamp source fetch --version <latestVersion> works with the CalVer version string
• Verify the agent correctly handles: up-to-date (skips), outdated with fix (reports), outdated without fix (proceeds), source fetch failure (proceeds)
• Verify feature/security workflows are unaffected

🤖 Generated with Claude Code

[github-actions]

Code Review

Blocking Issues

None.

Suggestions

1. Lost .swamp.yaml config snippet (swamp-repo/SKILL.md): The removed "Custom Datastores" section included a .swamp.yaml configuration example (type: / config: fields) that showed how third-party datastores are declared. The new one-liner points to swamp-extension, which covers creating extensions — but the YAML config example was useful for consuming them. Consider adding a brief snippet back to the SKILL.md or to a reference file. Not blocking since swamp help datastore and the extension docs cover it.

Notes

CLAUDE.md compliance:

• SKILL.md files are uppercase ✓
• Frontmatter present with name + description ✓
• swamp-issue/SKILL.md: 231 lines (under 500 limit) ✓
• swamp-repo/SKILL.md: 402 lines (under 500 limit) ✓
• No extraneous files ✓
• Content correctly split between SKILL.md and references/ files ✓

State machine design (swamp-issue bug workflow): Well-structured Gate/Action/Verify/On Failure pattern. The defensive failure handling (all errors → inconclusive → proceed to submit) is exactly right — never blocks the user from filing. The "prefer inconclusive over bug_fixed" guidance in version_check.md is a good safety rail.

swamp-repo refactoring: Clean extraction of Lock Internals, --skip-migration details, and Legacy Extension Layout Migration into references/troubleshooting.md. The added verification steps (confirm source loaded after extension source add, verify lock cleared after release) are practical improvements.

DDD: No domain code changes — skill documentation only. No DDD concerns.

Security: No executable code changes. CLI commands referenced in the skill are standard swamp commands with no injection vectors.