chore: clean up repo for public release

- Remove BMAD framework, IDE configs, dev screenshots, test files,
  internal docs, and backup files
- Rename keep-notes/ to memento-note/
- Update all references from keep-notes to memento-note
- Add Apache 2.0 license with Commons Clause (non-commercial restriction)
- Add clean .gitignore and .env.docker.example

memento-note/hooks/use-reminder-check.ts

@@ -0,0 +1,53 @@
+'use client';
+
+import { useEffect, useRef } from 'react';
+import { Note } from '@/lib/types';
+import { toast } from 'sonner';
+
+const STORAGE_KEY = 'memento-notified-reminders';
+
+function getNotifiedFromStorage(): Set<string> {
+  try {
+    const raw = sessionStorage.getItem(STORAGE_KEY);
+    return raw ? new Set(JSON.parse(raw)) : new Set();
+  } catch {
+    return new Set();
+  }
+}
+
+function persistNotified(ids: Set<string>) {
+  try {
+    sessionStorage.setItem(STORAGE_KEY, JSON.stringify([...ids]));
+  } catch { /* quota exceeded — non-critical */ }
+}
+
+export function useReminderCheck(notes: Note[]) {
+  const notifiedRef = useRef<Set<string>>(getNotifiedFromStorage());
+
+  useEffect(() => {
+    const checkReminders = () => {
+      const now = new Date();
+      const newIds: string[] = [];
+
+      for (const note of notes) {
+        if (!note.reminder || note.isReminderDone) continue;
+        if (notifiedRef.current.has(note.id)) continue;
+
+        const reminderDate = new Date(note.reminder);
+        if (reminderDate <= now) {
+          newIds.push(note.id);
+          toast.info(`🔔 ${note.title || 'Untitled Note'}`, { id: `reminder-${note.id}` });
+        }
+      }
+
+      if (newIds.length > 0) {
+        for (const id of newIds) notifiedRef.current.add(id);
+        persistNotified(notifiedRef.current);
+      }
+    };
+
+    checkReminders();
+    const interval = setInterval(checkReminders, 30_000);
+    return () => clearInterval(interval);
+  }, [notes]);
+}