feat: add CSS Cubic-Bezier easing curve generator utility

[TweenzY-Y]

📝 Description

Adds a new CSS Cubic-Bezier Generator to the Dev Utilities section. It lets you design custom cubic-bezier() easing curves visually and copy ready-to-use CSS.

Highlights

• Interactive SVG graph with two draggable control points (X locked to [0, 1], Y free for overshoot).
• Presets: linear, ease, ease-in, ease-out, ease-in-out.
• Play/Stop animation preview that compares your curve against a selected preset; duration adjustable (0.5s–5s).
• Copyable .custom-transition { ... } CSS block.
• Fully offline, no external libraries. Registered under /devutilities/cubic-bezier.

🔗 Related Issue

Closes #408

🎯 Type of Change

• fix: Bug fix
• feat: New feature
• style: UI/Theme changes (Monochrome)
• chore: Build/Maintenance

✅ Checklist

• Follows project's Monochrome design (Black/Grey/White) 🎨
• Follows Conventional Commits 📜
• Added screenshots (if UI was changed) 📸
• Tested locally on the latest version 🧪

[vercel]

@TweenzY-Y is attempting to deploy a commit to the shamilahmdt's projects Team on Vercel.

A member of the Team first needs to authorize it.

[github-actions]

👋 Hello, @TweenzY-Y!

Thank you for your contribution to DevTasks.

The maintainer has been notified and will review your pull request shortly. If any changes are needed, we will let you know in the comments below.