added Feedback page, added braindump backend

hooks/firebase/useDeleteNote.ts

@@ -0,0 +1,39 @@
+import { useAuthContext } from "@/contexts/AuthContext";
+import { useMutation, useQueryClient } from "react-query";
+import firestore from "@react-native-firebase/firestore";
+
+export const useDeleteNote = () => {
+  const { user: currentUser } = useAuthContext();
+  const queryClient = useQueryClient();
+
+  return useMutation({
+    mutationKey: ["deleteNote"],
+    mutationFn: async (noteId: string) => {
+      try {
+        const snapshot = await firestore()
+          .collection("BrainDumps")
+          .where("id", "==", noteId)
+          .get();
+
+        if (snapshot.empty) {
+          throw new Error("Note not found");
+        }
+
+        const docId = snapshot.docs[0].id;
+
+        const noteData = snapshot.docs[0].data();
+        if (noteData.creatorId !== currentUser?.uid) {
+          throw new Error("Unauthorized: You can only delete your own Note");
+        }
+
+        await firestore().collection("BrainDumps").doc(docId).delete();
+      } catch (e) {
+        console.error("Error deleting note: ", e);
+        throw e;
+      }
+    },
+    onSuccess: () => {
+      queryClient.invalidateQueries("braindumps");
+    },
+  });
+};