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_client.rs

@@ -3,6 +3,8 @@ use std::collections::BTreeMap;
 use crate::config::{McpOAuthConfig, McpServerConfig, ScopedMcpServerConfig};
 use crate::mcp::{mcp_server_signature, mcp_tool_prefix, normalize_name_for_mcp};
 
+pub const DEFAULT_MCP_TOOL_CALL_TIMEOUT_MS: u64 = 60_000;
+
 #[derive(Debug, Clone, PartialEq, Eq)]
 pub enum McpClientTransport {
     Stdio(McpStdioTransport),
@@ -18,6 +20,7 @@ pub struct McpStdioTransport {
     pub command: String,
     pub args: Vec<String>,
     pub env: BTreeMap<String, String>,
+    pub tool_call_timeout_ms: Option<u64>,
 }
 
 #[derive(Debug, Clone, PartialEq, Eq)]
@@ -75,6 +78,7 @@ impl McpClientTransport {
                 command: config.command.clone(),
                 args: config.args.clone(),
                 env: config.env.clone(),
+                tool_call_timeout_ms: config.tool_call_timeout_ms,
             }),
             McpServerConfig::Sse(config) => Self::Sse(McpRemoteTransport {
                 url: config.url.clone(),
@@ -105,6 +109,14 @@ impl McpClientTransport {
     }
 }
 
+impl McpStdioTransport {
+    #[must_use]
+    pub fn resolved_tool_call_timeout_ms(&self) -> u64 {
+        self.tool_call_timeout_ms
+            .unwrap_or(DEFAULT_MCP_TOOL_CALL_TIMEOUT_MS)
+    }
+}
+
 impl McpClientAuth {
     #[must_use]
     pub fn from_oauth(oauth: Option<McpOAuthConfig>) -> Self {
@@ -136,6 +148,7 @@ 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: Some(15_000),
             }),
         };
 
@@ -154,6 +167,7 @@ mod tests {
                     transport.env.get("TOKEN").map(String::as_str),
                     Some("secret")
                 );
+                assert_eq!(transport.tool_call_timeout_ms, Some(15_000));
             }
             other => panic!("expected stdio transport, got {other:?}"),
         }