codeSplitters: an API reference (or Worker MCP server) so someone can build their own UI #379

Follow-up to the WebMCP tools: those let an agent drive the existing page. Building a different UI needs every read and action documented in one place: the palette's api strings plus the read routes (tree, file, blame, branches, the file WebSocket). Options: a generated API reference, or an MCP server on the Worker so agents outside the browser can use it too.