🚀 Feature: Auto-Save Notes with Debounce

[shreyaB7134]

📌 Description

Currently, users must manually click "Save" to store their notes. This can lead to data loss if they accidentally close the browser or navigate away.
I propose implementing an auto-save feature that saves the note content automatically while the user is typing, using a debounce function to prevent excessive saves (e.g., after 1.5s of inactivity).

✅ Tasks

Add a JavaScript event listener to the textarea field.
Use setTimeout and clearTimeout to implement debounce.
Send the note content via fetch() to /dashboard/autosave (mock for now).
Show a "Saving..." or "Saved ✅" message to indicate status.

@soumya813 review my issue