New MCP tools for reading and searching merge requests

You can now use get_merge_request to retrieve a merge request along with its diffs, commits, notes, pipelines, or discussions in a single call, so your AI agent no longer has to chain multiple requests to get the full picture of an MR.

You can also use the new list_merge_requests tool to search and filter merge requests by author, assignee, reviewer, state, labels, or free-text query, making it easy to find exactly the MRs you care about without leaving your workflow.