feat(notes): integrate Quill rich text editor for add, edit, and view…

[rishaan007]

This PR replaces the plain <textarea> with a Quill.js rich text editor
for improved note formatting (bold, italic, links, lists, etc.).

✅ Added Quill.js in add.ejs
✅ Synced editor content into hidden input
✅ Preserves formData when validation errors occur

[rishaan007]

This PR adds support for rich text editing using Quill:

• Integrated Quill in add.ejs
• Created edit.ejs with Quill editor

Enhances note editing and viewing experience.

[rishaan007]

✨ Summary of Changes
📝 Features Added
New Dashboard Controller Function
Implemented dashboardAddNotePost in dashboardController.js
Allows users to add new notes with title and body
Associates note with logged-in user (req.user.id)
Redirects to /dashboard with success message
🎨 Styling Updates
Quill Editor Custom Styles (main.css)
Added minimum height for better usability
White background for clean appearance
Rounded corners and subtle border for modern UI
✅ Improvements
Enhanced user experience for creating notes
Better readability and consistency in the rich-text editor
📌 How to Test
Go to the dashboard and create a new note.
Verify that the note is saved correctly.
Check that a success message appears.
Open the Quill editor.
Confirm it has min-height, white background, rounded borders, and gray border.