webchat: show real ws errors

apps/macos/Sources/Clawdis/Resources/WebChat/format-error.js

@@ -0,0 +1,31 @@
+// Shared formatter for WebChat bootstrap errors so UI shows actionable messages.
+export const formatError = (err) => {
+  if (!err) return "Unknown error";
+  if (err instanceof Error) return err.stack || err.message || String(err);
+
+  const isCloseEvent =
+    (typeof CloseEvent !== "undefined" && err instanceof CloseEvent) ||
+    (typeof err?.code === "number" &&
+      (err?.reason !== undefined || err?.wasClean !== undefined));
+  if (isCloseEvent) {
+    const reason = err.reason?.trim();
+    const parts = [`WebSocket closed (${err.code})`];
+    if (reason) parts.push(`reason: ${reason}`);
+    if (err.wasClean) parts.push("clean close");
+    return parts.join("; ");
+  }
+
+  const isWsErrorEvent =
+    err?.type === "error" && typeof err?.target?.readyState === "number";
+  if (isWsErrorEvent) {
+    const states = ["connecting", "open", "closing", "closed"];
+    const stateLabel = states[err.target.readyState] ?? err.target.readyState;
+    return `WebSocket error (state: ${stateLabel})`;
+  }
+
+  try {
+    return JSON.stringify(err);
+  } catch {
+    return String(err);
+  }
+};