feat(raw-api): register gitea_request tool and wire server dispatch

Registers gitea_request in AVAILABLE_TOOLS with write_operation=False
(deliberate: a static flag cannot describe a read-or-write tool; the handler
authorizes writes per-method) and maps the tool name to raw_api_request_tool in
the server handler registry.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

src/aegis_gitea_mcp/mcp_protocol.py

@@ -718,6 +718,38 @@ AVAILABLE_TOOLS: list[MCPTool] = [
         },
         write_operation=True,
     ),
+    _tool(
+        "gitea_request",
+        (
+            "Generic escape hatch that calls an arbitrary Gitea REST endpoint "
+            "(method + path). Prefer the dedicated tools; use this only for "
+            "endpoints they do not cover. Subject to policy, write-mode and the "
+            "sensitive-path denylist. Methods other than GET/HEAD are writes and "
+            "require write-mode plus a whitelisted repository."
+        ),
+        {
+            "type": "object",
+            "properties": {
+                "method": {
+                    "type": "string",
+                    "enum": ["GET", "HEAD", "POST", "PUT", "PATCH", "DELETE"],
+                },
+                "path": {
+                    "type": "string",
+                    "description": "Gitea REST path, e.g. /repos/{owner}/{repo}/pulls/1/merge",
+                },
+                "query": {"type": "object", "description": "Optional query-string parameters"},
+                "body": {"type": "object", "description": "Optional JSON request body"},
+            },
+            "required": ["method", "path"],
+            "additionalProperties": False,
+        },
+        # write_operation is intentionally False: a static flag cannot describe a
+        # tool that is read OR write depending on the method. Setting it True
+        # would force the central write-mode gate on GETs and break reads. The
+        # handler is authoritative via its own per-method authorize() call.
+        write_operation=False,
+    ),
 ]