Refactor form components and improve API error handling

webui/src/lib/errorUtils.ts

@@ -0,0 +1,32 @@
+/**
+ * Parses error response from API calls and returns a formatted error message
+ */
+export async function parseErrorResponse(response: Response): Promise<string> {
+  let errorMessage = `HTTP ${response.status}`
+
+  try {
+    const errorText = await response.text()
+    if (errorText) {
+      errorMessage += `: ${errorText}`
+    }
+  } catch {
+    // If we can't read the error, just use status
+  }
+
+  return errorMessage
+}
+
+/**
+ * Handles common API call errors and throws appropriate Error objects
+ */
+export async function handleApiError(response: Response): Promise<void> {
+  // Handle authentication errors
+  if (response.status === 401) {
+    throw new Error('Authentication required')
+  }
+
+  if (!response.ok) {
+    const errorMessage = await parseErrorResponse(response)
+    throw new Error(errorMessage)
+  }
+}