add release-notes skill

plugin/skills/github-release-notes/SKILL.md

@@ -0,0 +1,77 @@
+---
+name: github-release-notes
+description: >
+  This skill should be used when the user asks to "write release notes", "generate a changelog",
+  "cut a release", "tag a version", "what shipped since", "summarize the last N commits for a
+  release", "update CHANGELOG.md", or asks for a version bump. Also triggers on "release notes
+  for v1.2", "draft the release", and "what changed between tags".
+metadata:
+  version: "0.1.0"
+---
+
+# Release Notes + Changelog
+
+Turn merged work into release notes a human wants to read, then publish them.
+
+## Determine the range
+
+1. `get_latest_release` or `list_tags` for the previous boundary.
+2. `list_commits` with `since` the previous tag's date, or compare against the tag SHA.
+3. `search_pull_requests` with `repo:owner/name is:merged base:main` in the window — merged PR titles and bodies are far better source material than raw commit subjects.
+
+If the repo has no prior release, use the first commit as the boundary and say so.
+
+## Version number
+
+Semver, decided by content, not by habit:
+
+- **MAJOR** — a breaking API change, a removed endpoint, a contract storage layout change, or a migration that is not backward compatible.
+- **MINOR** — new user-visible capability, additive and backward compatible.
+- **PATCH** — fixes and internals only.
+
+Pre-1.0 repos: breaking changes go in MINOR. State the reasoning in one line so the user can override.
+
+## Structure
+
+```markdown
+## [1.4.0] — 2026-07-30
+
+### Added
+- Short, user-outcome-first line. (#128)
+
+### Changed
+- What is different now, and what the reader must do about it. (#131)
+
+### Fixed
+- The symptom the user experienced, not the internal cause. (#134)
+
+### Security
+- Disclosed issue and its severity. (#136)
+
+### Breaking
+- The change, the migration step, and the deadline. (#139)
+```
+
+Omit empty sections. Always link the PR number. Order sections Breaking → Security → Added → Changed → Fixed when a breaking change is present.
+
+## Writing rules
+
+- Lead with the user-visible outcome. "Markets now settle in under 4 seconds" beats "Refactored settlement queue."
+- One line per change. If a change needs two lines, it needs its own subsection.
+- Specific numbers over adjectives. "3.1s → 0.4s median" not "significantly faster."
+- Active voice, present tense.
+- No filler. Banned: leverage, synergy, ecosystem play, game-changing.
+- Internal-only refactors with zero user-visible effect go in a collapsed "Internal" section or are omitted entirely.
+
+## MAD Gambit constraint
+
+If the release touches anything user- or investor-facing, canonical numbers are frozen: platform fee 1.88%, community profit share 28.8%, creator revenue share 40%, seed raise $1–2M at $12M pre-money. Never restate them with different values, and never round the fee. Platform name is "MAD Gambit"; the card game line is "MADHAT's Gambit".
+
+## Publishing
+
+1. Update `CHANGELOG.md` — prepend the new section, keep the Keep-a-Changelog format if the file already uses it, preserve the existing link-reference block at the bottom.
+2. Commit on a `chore/release-vX.Y.Z` branch (see `github-repo-ops` for the write sequence).
+3. Create the tag and GitHub Release with the same body. Mark it prerelease when the version has a `-rc`/`-beta` suffix.
+4. Return the release URL.
+
+Do not publish a release until the user confirms the version number and the notes. Draft first.