Import mcp-to-cli from the rhema workspace

The crate maps MCP tool catalogs to clap commands and back, and has no
rhema dependencies — it was in-tree only because the workspace glob
reached it. Its own repository gives it its own release cadence and
its own crates.io token, scoped to this crate alone.

tests/fixtures/update_pull_request.json

@@ -0,0 +1,57 @@
+{
+  "properties": {
+    "base": {
+      "description": "New base branch name",
+      "type": "string"
+    },
+    "body": {
+      "description": "New description",
+      "type": "string"
+    },
+    "draft": {
+      "description": "Mark pull request as draft (true) or ready for review (false)",
+      "type": "boolean"
+    },
+    "maintainer_can_modify": {
+      "description": "Allow maintainer edits",
+      "type": "boolean"
+    },
+    "owner": {
+      "description": "Repository owner",
+      "type": "string"
+    },
+    "pullNumber": {
+      "description": "Pull request number to update",
+      "type": "number"
+    },
+    "repo": {
+      "description": "Repository name",
+      "type": "string"
+    },
+    "reviewers": {
+      "description": "GitHub usernames or ORG/team-slug team reviewers to request reviews from",
+      "items": {
+        "type": "string"
+      },
+      "type": "array"
+    },
+    "state": {
+      "description": "New state",
+      "enum": [
+        "open",
+        "closed"
+      ],
+      "type": "string"
+    },
+    "title": {
+      "description": "New title",
+      "type": "string"
+    }
+  },
+  "required": [
+    "owner",
+    "repo",
+    "pullNumber"
+  ],
+  "type": "object"
+}