fix: strip id/system fields before creating PB records

lib/pb.ts

@@ -86,11 +86,13 @@ export async function createRecord<T extends PBRecord>(
   collection: string,
   fields: Record<string, unknown>,
 ): Promise<T> {
+  // Strip id/system fields — let PB auto-generate them.
+  const { id: _id, created: _c, updated: _u, ...safeFields } = fields;
   const url = `${BASE_URL}/api/collections/${collection}/records`;
   const res = await fetch(url, {
     method: "POST",
     headers: { Authorization: TOKEN as string, "Content-Type": "application/json" },
-    body: JSON.stringify(fields),
+    body: JSON.stringify(safeFields),
     cache: "no-store",
   });
   if (!res.ok) {