v0.1.0

Initial mdgarden project scaffold

Add the complete mdgarden project scaffold: source code (src/), client runtime, plugins, build + CLI, tests and fixtures, theme assets, and example starter. Include package.json, package-lock, TypeScript configs, scripts for building/SEA packaging, Homebrew formula, Dockerfile, install scripts, and helper tooling. Add documentation (README, CONTRIBUTING), GPL-3.0 license, and CI/release automation (GitHub Actions for CI and multi-channel releases: npm, binaries, Docker, Homebrew).