fix: normalize googlechat targets

extensions/googlechat/src/targets.ts

@@ -6,8 +6,8 @@ export function normalizeGoogleChatTarget(raw?: string | null): string | undefin
   if (!trimmed) return undefined;
   const withoutPrefix = trimmed.replace(/^(googlechat|google-chat|gchat):/i, "");
   const normalized = withoutPrefix
-    .replace(/^user:/i, "users/")
-    .replace(/^space:/i, "spaces/");
+    .replace(/^user:(users\/)?/i, "users/")
+    .replace(/^space:(spaces\/)?/i, "spaces/");
   if (isGoogleChatUserTarget(normalized)) {
     const suffix = normalized.slice("users/".length);
     return suffix.includes("@") ? `users/${suffix.toLowerCase()}` : normalized;