Fix SSE server connection handling for MCP client

### Summary
This PR improves the MCP (Model Context Protocol) client's SSE (Server-Sent Events) server connection handling by replacing the generic string parameter with a proper `SseServerParameters` class.

### Changes
- **Breaking Change**: Changed `server_params` type from `Union[StdioServerParameters, str]` to `Union[StdioServerParameters, SseServerParameters]`
- Added import for `SseServerParameters` from `mcp.client.session_group`
- Updated SSE client connection to use structured parameters instead of a simple URL string
- Fixed error message to correctly reflect the expected parameter types
- Improved logging by changing info-level log to debug-level for consistency

### Details

#### Before
The SSE client connection only accepted a URL string:
```python
async with self._client(self._server_params) as (read, write):
```

#### After
Now properly unpacks SSE server parameters:
```python
async with self._client(
    url=self._server_params.url,
    headers=self._server_params.headers,
    timeout=self._server_params.timeout,
    sse_read_timeout=self._server_params.sse_read_timeout
) as (read, write):
```

### Benefits
- **Type Safety**: Stronger type checking with dedicated `SseServerParameters` class
- **Extended Configuration**: Support for custom headers (authentication), timeouts, and SSE-specific settings
- **Better Error Messages**: Clear type error messages when incorrect parameters are provided
- **Improved Debugging**: Debug logging of SSE server parameters for troubleshooting

### Migration Guide
Users need to update their SSE server initialization:
```python
# Before
client = MCPClient("https://example.com/sse")

# After
from mcp.client.session_group import SseServerParameters
client = MCPClient(SseServerParameters(
    url="https://example.com/sse",
    headers={"Authorization": "Bearer token"},
    timeout=30,
    sse_read_timeout=60
))
```

### Testing
- [ ] Tested with StdioServerParameters (unchanged behavior)
- [ ] Tested with SseServerParameters with various configurations
- [ ] Verified error handling for invalid parameter types

---

This is a necessary change to support production-ready SSE connections with proper authentication and timeout handling.

src/pipecat/services/mcp_service.py

@@ -8,8 +8,8 @@ from pipecat.adapters.schemas.tools_schema import ToolsSchema
 from pipecat.utils.base_object import BaseObject
 
 try:
-    from mcp import ClientSession, StdioServerParameters, types
-    from mcp.client.session import ClientSession
+    from mcp import ClientSession, StdioServerParameters
+    from mcp.client.session_group import SseServerParameters
     from mcp.client.sse import sse_client
     from mcp.client.stdio import stdio_client
 except ModuleNotFoundError as e:
@@ -21,7 +21,7 @@ except ModuleNotFoundError as e:
 class MCPClient(BaseObject):
     def __init__(
         self,
-        server_params: Union[StdioServerParameters, str],
+        server_params: Union[StdioServerParameters, SseServerParameters],
         **kwargs,
     ):
         super().__init__(**kwargs)
@@ -30,12 +30,12 @@ class MCPClient(BaseObject):
         if isinstance(server_params, StdioServerParameters):
             self._client = stdio_client
             self._register_tools = self._stdio_register_tools
-        elif isinstance(server_params, str):
+        elif isinstance(server_params, SseServerParameters):
             self._client = sse_client
             self._register_tools = self._sse_register_tools
         else:
             raise TypeError(
-                f"{self} invalid argument type: `server_params` must be either StdioServerParameters or an SSE server url string."
+                f"{self} invalid argument type: `server_params` must be either StdioServerParameters or SseServerParameters."
             )
 
     async def register_tools(self, llm) -> ToolsSchema:
@@ -90,7 +90,12 @@ class MCPClient(BaseObject):
             logger.debug(f"Executing tool '{function_name}' with call ID: {tool_call_id}")
             logger.trace(f"Tool arguments: {json.dumps(arguments, indent=2)}")
             try:
-                async with self._client(self._server_params) as (read, write):
+                async with self._client(
+                    url=self._server_params.url,
+                    headers=self._server_params.headers,
+                    timeout=self._server_params.timeout,
+                    sse_read_timeout=self._server_params.sse_read_timeout
+                ) as (read, write):
                     async with self._session(read, write) as session:
                         await session.initialize()
                         await self._call_tool(session, function_name, arguments, result_callback)
@@ -98,12 +103,16 @@ class MCPClient(BaseObject):
                 error_msg = f"Error calling mcp tool {function_name}: {str(e)}"
                 logger.error(error_msg)
                 logger.exception("Full exception details:")
-                await result_callback(error_msg)
-
-        logger.debug("Starting registration of mcp.run tools")
-        tool_schemas: List[FunctionSchema] = []
-
-        async with self._client(self._server_params) as (read, write):
+                await result_callback(error_msg)\
+            
+        logger.debug(f"SSE server parameters: {self._server_params}")
+        
+        async with self._client(
+            url=self._server_params.url,
+            headers=self._server_params.headers,
+            timeout=self._server_params.timeout,
+            sse_read_timeout=self._server_params.sse_read_timeout
+        ) as (read, write):
             async with self._session(read, write) as session:
                 await session.initialize()
                 tools_schema = await self._list_tools(session, mcp_tool_wrapper, llm)