fix(slurm): add default 30s timeout to HTTP client

Replaces http.DefaultClient with a client that has a 30s timeout to prevent indefinite hangs when the Slurm REST API is unresponsive.

Ultraworked with [Sisyphus](https://github.com/code-yeongyu/oh-my-openagent)

Co-authored-by: Sisyphus <clio-agent@sisyphuslabs.ai>

internal/slurm/options.go

@@ -24,6 +24,8 @@ func defaultClientConfig() *clientConfig {
 	}
 }
 
+const defaultHTTPTimeout = 30 * time.Second
+
 // WithJWTKey specifies the path to the JWT key file.
 func WithJWTKey(path string) ClientOption {
 	return func(c *clientConfig) error {
@@ -89,11 +91,12 @@ func NewClientWithOpts(baseURL string, opts ...ClientOption) (*Client, error) {
 		}
 
 		tr := NewJWTAuthTransport(cfg.username, key, transportOpts...)
-		httpClient = tr.Client()
+		httpClient = &http.Client{
+			Transport: tr,
+			Timeout:   defaultHTTPTimeout,
+		}
 	} else if cfg.httpClient != nil {
 		httpClient = cfg.httpClient
-	} else {
-		httpClient = http.DefaultClient
 	}
 
 	return NewClient(baseURL, httpClient)