Add Bun TypeScript markado CLI

[halkn]

Summary

• Implement the Bun + TypeScript markado CLI, local HTTP API, wiki tree scanning, Markdown rendering, and vanilla browser UI.
• Add GitHub Actions CI and tag-driven release workflow for platform binaries.
• Add version update/check scripts, Codex command rules, pinned Bun version, tag/version validation, and symlink-safe path checks.

Validation

• bun run check
• bun build src/cli.ts --compile --target=bun-linux-x64 --outfile dist/markado-linux-x64
• dist/markado-linux-x64 --version