feat: add project release and run tests skills documentation

- Introduced SKILL.md files for project release and running tests in the duty-teller project.
- Documented the project release workflow, including steps for updating CHANGELOG, committing changes, and tagging releases.
- Provided instructions for running backend (pytest) and frontend (Vitest) tests, including prerequisites and failure handling.
- Enhanced user guidance for verifying changes and ensuring test coverage.

.cursor/skills/project-release/SKILL.md

@@ -0,0 +1,55 @@
+---
+name: project-release
+description: Performs a project release by updating CHANGELOG for the new version, committing all changes, and pushing a version tag. Use when the user asks to release, cut a release, publish a version, or to update changelog and push a tag.
+---
+
+# Project Release
+
+Release workflow for duty-teller: update changelog, commit, tag, and push. Triggers Gitea Actions (Docker build) on `v*` tags.
+
+## Prerequisites
+
+- Decide the **new version** (e.g. `2.1.0`). Use [Semantic Versioning](https://semver.org/).
+- Ensure `CHANGELOG.md` has entries under `## [Unreleased]` (or add a short note like "No changes" if intentional).
+
+## Steps
+
+### 1. Update CHANGELOG.md
+
+- Replace the `## [Unreleased]` section with a dated release section:
+  - `## [X.Y.Z] - YYYY-MM-DD` (use today's date in `YYYY-MM-DD`).
+- Leave a new empty `## [Unreleased]` section after it (for future edits).
+- At the bottom of the file, add the comparison link for the new version:
+  - `[X.Y.Z]: https://github.com/your-org/duty-teller/releases/tag/vX.Y.Z`
+  - (Replace `your-org/duty-teller` with the real repo URL if different.)
+- Update the `[Unreleased]` link to compare against this release, e.g.:
+  - `[Unreleased]: https://github.com/your-org/duty-teller/compare/vX.Y.Z...HEAD`
+
+Format follows [Keep a Changelog](https://keepachangelog.com/en/1.1.0/); keep existing subsections (Added, Changed, Security, etc.) under the new version.
+
+### 2. Bump version in pyproject.toml (optional)
+
+- Set `version = "X.Y.Z"` in `[project]` so it matches the release. Skip if the project does not sync version here.
+
+### 3. Commit and tag
+
+- Stage all changes: `git add -A`
+- Commit with Conventional Commits: `git commit -m "chore(release): vX.Y.Z"`
+- Create annotated tag: `git tag -a vX.Y.Z -m "Release vX.Y.Z"`
+- Push branch: `git push origin main` (or current branch)
+- Push tag: `git push origin vX.Y.Z`
+
+Pushing the `v*` tag triggers `.gitea/workflows/docker-build.yml` (Docker build and release).
+
+## Checklist
+
+- [ ] CHANGELOG: `[Unreleased]` → `[X.Y.Z] - YYYY-MM-DD`, new empty `[Unreleased]`, links at bottom updated
+- [ ] pyproject.toml version set to X.Y.Z (if used)
+- [ ] `git add -A` && `git commit -m "chore(release): vX.Y.Z"`
+- [ ] `git tag -a vX.Y.Z -m "Release vX.Y.Z"`
+- [ ] `git push origin main` && `git push origin vX.Y.Z`
+
+## Notes
+
+- Do not push tags from unreleased or uncommitted changelog.
+- If the repo URL in CHANGELOG links is a placeholder, keep it or ask the user for the correct base URL.