feat: add remotion-best-practices skill from remotion-dev/skills

Imported official Remotion skill for video creation in React:
- 28 modular rule files covering animations, audio, video, captions, 3D, etc.
- Added author (remotion-dev) and version (1.0) metadata
- Updated skill count: 224 → 225
- Regenerated skills_index.json

Source: https://github.com/remotion-dev/skills

skills/remotion-best-practices/rules/tailwind.md

@@ -0,0 +1,11 @@
+---
+name: tailwind
+description: Using TailwindCSS in Remotion.
+metadata:
+---
+
+You can and should use TailwindCSS in Remotion, if TailwindCSS is installed in the project.
+
+Don't use `transition-*` or `animate-*` classes - always animate using the `useCurrentFrame()` hook.  
+
+Tailwind must be installed and enabled first in a Remotion project - fetch  https://www.remotion.dev/docs/tailwind using WebFetch for instructions.