Peggy Publish title parser

Chose Peggy 5.1.0 over Nearley, PEG.js, or a hand-written parser because it is the maintained PEG.js successor and generates a committed CommonJS parser at build time without a runtime parser dependency. src/modules/publish-issue-title.peggy is the canonical syntax grammar; generate publish-issue-title.js through the project script. Keep semantic workspace/path resolution outside the parser: a compact suffix is classified only after checkout of the CI-approved revision. Preserve legacy JSON-qualified title parsing for compatibility.