feat(chat): sync multi-role backend APIs

src/data/services/api/character_error_code.ts

@@ -0,0 +1,36 @@
+import { ApiError } from "./api_result";
+
+export const CHARACTER_ERROR_CODES = [
+  "CHARACTER_DISABLED",
+  "CHARACTER_NOT_FOUND",
+  "CHARACTER_MISMATCH",
+  "CHARACTER_STATE_UNAVAILABLE",
+] as const;
+
+export type CharacterErrorCode = (typeof CHARACTER_ERROR_CODES)[number];
+
+export function getCharacterErrorCode(error: unknown): CharacterErrorCode | null {
+  let current = error;
+  for (let depth = 0; depth < 5 && current; depth += 1) {
+    if (current instanceof ApiError) {
+      const code = readErrorCode(current.details);
+      if (isCharacterErrorCode(code)) return code;
+    }
+    current = current instanceof Error ? current.cause : null;
+  }
+  return null;
+}
+
+function readErrorCode(value: unknown): unknown {
+  if (!value || typeof value !== "object") return null;
+  const data = value as Record<string, unknown>;
+  if (typeof data.errorCode === "string") return data.errorCode;
+  return readErrorCode(data.detail) ?? readErrorCode(data.data);
+}
+
+function isCharacterErrorCode(value: unknown): value is CharacterErrorCode {
+  return (
+    typeof value === "string" &&
+    (CHARACTER_ERROR_CODES as readonly string[]).includes(value)
+  );
+}