ci: add cocogitto for conventional commits and automated releases

- Add cog.toml with commit type configs and version bump hooks
- Add .woodpecker.yml pipeline for automated version bumping on main
- Add Version element to csproj for cog to update
- Document cog workflow in CLAUDE.md

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

.woodpecker.yml

@@ -0,0 +1,43 @@
+when:
+  - event: push
+    branch: main
+
+steps:
+  - name: release
+    image: alpine:latest
+    # Skip if this is a version bump commit (prevents infinite loop)
+    when:
+      - evaluate: 'CI_COMMIT_MESSAGE not contains "chore(release):"'
+    commands:
+      # Install dependencies
+      - apk add --no-cache git curl perl
+
+      # Install Cocogitto
+      - curl -sSL https://github.com/cocogitto/cocogitto/releases/latest/download/cocogitto-6.5.0-x86_64-unknown-linux-musl.tar.gz | tar xz
+      - mv cog /usr/local/bin/
+      - cog --version
+
+      # Configure Git
+      - git config --global user.name "woodpecker-ci[bot]"
+      - git config --global user.email "woodpecker-ci[bot]@noreply.local"
+      - git config --global --add safe.directory "$CI_WORKSPACE"
+
+      # Fetch full history (Woodpecker does shallow clone by default)
+      - git fetch --unshallow --tags || git fetch --tags
+
+      # Check if there are commits to bump
+      - |
+        if cog bump --auto --dry-run 2>&1 | grep -qE "(No conventional commits|already on)"; then
+          echo "No version bump needed"
+          exit 0
+        fi
+
+      # Bump version
+      - cog bump --auto
+
+      # Push changes and tags using PAT
+      - git remote set-url origin "https://x-access-token:$GITHUB_TOKEN@github.com/${CI_REPO}.git"
+      - git push origin HEAD:main
+      - git push origin --tags
+    secrets:
+      - GITHUB_TOKEN