v0.2.12 — Hub MCP bundled + one-touch MCP registration

The one-touch installer now registers the agentlas Hub MCP everywhere it installs the engine: Claude Code (bundled .mcp.json), Codex (rmcp client + config.toml), Gemini CLI (extension manifest), and Antigravity (mcp_config.json). No separate MCP setup step remains.

Also ships release version-sync tooling: scripts/bump-version.sh updates every pinned ref (scripts, READMEs in 5 languages, manifests, install SVGs, and the agentlas.cloud install command) in one command, and verify-install-docs.sh now fails on any stale version pin.