Add Skill / UI Tweaker Skill to frontend section

[dhosruiasn]

What this PR does

Adding dhosruiasn/ui-tweaker-skill to the Community Skills -> Development and Testing section.

About UI Tweaker Skill

UI Tweaker is an open-source visual control panel designed specifically for Vibe Coding. It bridges the gap between traditional flat design intuition and AI-driven frontend development. The skill suite provides:

• Visual DOM Manipulation: Figma-like sliders for margin, padding, and gap adjustments directly in the browser.
• Live Preview: Real-time visual feedback without needing to switch contexts or guess CSS values.
• Safe Code Injection: Auto-generates exact CSS/Tailwind updates and writes them safely back to the source code without breaking existing React or component logic.

Compatible with Claude Code, Cursor, Windsurf, and other standard agent environments.

Why this belongs in the list

While most UI-related skills focus on text-based prompt constraints or system instructions, UI Tweaker introduces a visual feedback loop. It solves a core friction point in Vibe Coding: the tedious trial-and-error of asking AI to "move it a few pixels to the left." By injecting a visual interface, it gives developers design superpowers and prevents AI-generated layout disasters.

Compliance with CONTRIBUTING.md

• Entry added to the correct section (Community Skills -> Development and Testing)
• Entry has author/repo prefix, working GitHub URL, brief description
• Repository has a working README/SKILL.md

Hope this brings value to the community. Thank you!