Initial commit: demo todo CLI with Claude Code setup

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

.claude/skills/changelog/SKILL.md

@@ -0,0 +1,9 @@
+---
+name: changelog
+description: Draft a changelog entry from the git commits since the last tag (or all commits if there is no tag). Use when the user asks for release notes or a changelog.
+---
+
+1. Find the range: `git describe --tags --abbrev=0` — if it fails, use the full history.
+2. Read the commits in that range with `git log --oneline <range>`.
+3. Group them under **Added**, **Changed**, **Fixed** (skip empty groups), one bullet per user-visible change, in plain language.
+4. Print the entry. Only write it to `CHANGELOG.md` if the user asks.