feat(mcp): add toolCallTimeoutMs, timeout/reconnect/error handling

- Add toolCallTimeoutMs to stdio MCP config with 60s default
- tools/call runs under timeout with dedicated Timeout error
- Handle malformed JSON/broken protocol as InvalidResponse
- Reset/reconnect stdio state on child exit or transport drop
- Add tests: slow timeout, invalid JSON response, stdio reconnect
- Verified: cargo test -p runtime 113 passed, clippy clean

rust/crates/runtime/src/mcp.rs

@@ -84,10 +84,13 @@ pub fn mcp_server_signature(config: &McpServerConfig) -> Option<String> {
 pub fn scoped_mcp_config_hash(config: &ScopedMcpServerConfig) -> String {
     let rendered = match &config.config {
         McpServerConfig::Stdio(stdio) => format!(
-            "stdio|{}|{}|{}",
+            "stdio|{}|{}|{}|{}",
             stdio.command,
             render_command_signature(&stdio.args),
-            render_env_signature(&stdio.env)
+            render_env_signature(&stdio.env),
+            stdio
+                .tool_call_timeout_ms
+                .map_or_else(String::new, |timeout_ms| timeout_ms.to_string())
         ),
         McpServerConfig::Sse(remote) => format!(
             "sse|{}|{}|{}|{}",
@@ -245,6 +248,7 @@ mod tests {
             command: "uvx".to_string(),
             args: vec!["mcp-server".to_string()],
             env: BTreeMap::from([("TOKEN".to_string(), "secret".to_string())]),
+            tool_call_timeout_ms: None,
         });
         assert_eq!(
             mcp_server_signature(&stdio),