fix(python): remove 30s default timeout from JsonRpcClient.request()

The Python SDK's JsonRpcClient.request() had a hardcoded 30s default
timeout via asyncio.wait_for(), unlike the other three SDK languages
(Go, Node/TS, .NET) which all wait indefinitely for the server to
respond.

Change the default from timeout=30.0 to timeout=None so that requests
wait indefinitely by default, matching the behavior of the other SDKs.
Callers can still pass an explicit timeout when needed.

Fixes #539

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

Author: SteveSandersonMS

python/copilot/jsonrpc.py

@@ -104,22 +104,23 @@ async def stop(self):
             self._stderr_thread.join(timeout=1.0)
 
     async def request(
-        self, method: str, params: Optional[dict] = None, timeout: float = 30.0
+        self, method: str, params: Optional[dict] = None, timeout: Optional[float] = None
     ) -> Any:
         """
         Send a JSON-RPC request and wait for response
 
         Args:
             method: Method name
             params: Optional parameters
-            timeout: Request timeout in seconds (default 30s)
+            timeout: Optional request timeout in seconds. If None (default),
+                waits indefinitely for the server to respond.
 
         Returns:
             The result from the response
 
         Raises:
             JsonRpcError: If server returns an error
-            asyncio.TimeoutError: If request times out
+            asyncio.TimeoutError: If request times out (only when timeout is set)
         """
         request_id = str(uuid.uuid4())
 
@@ -141,7 +142,9 @@ async def request(
         await self._send_message(message)
 
         try:
-            return await asyncio.wait_for(future, timeout=timeout)
+            if timeout is not None:
+                return await asyncio.wait_for(future, timeout=timeout)
+            return await future
         finally:
             with self._pending_lock:
                 self.pending_requests.pop(request_id, None)