[codey] Prepare v0.1.15 release

[Conalh]

Summary

• bumps package metadata and README Action usage to v0.1.15
• updates release metadata tests so the documented Action ref matches the release being prepared
• publishes the prebuilt Action runtime behavior from PR [codey] Run Action from bundled dist #29 under a versioned tag

Verification

• node --test test/workflow.test.mjs (red before version bump, green after)
• npm run build
• npm test (37/37)
• node dist/index.js audit --repo . --format json (rating none, 0 findings)
• node dist/index.js audit --repo test/fixtures/conflicted --format github
• git diff --check