docs: add Svelte to roadmap.md (#352)

This is not yet committing to a timeframe, but it is capturing a renderer we should be targeting.  Thanks!

Author: zeroasterisk

docs/roadmap.md

@@ -30,6 +30,7 @@ Key features:
 | **SwiftUI** | 📋 Planned | iOS/macOS | Planned for Q2 2026 |
 | **Jetpack Compose** | 📋 Planned | Android | Planned for Q2 2026 |
 | **Vue** | 💡 Proposed | Web | Community interest |
+| [**Svelte/Kit**](https://svelte.dev/docs/kit/introduction) | 💡 Proposed | Web | [Community interest](https://news.ycombinator.com/item?id=46287728) |
 | **ShadCN (React)** | 💡 Proposed | Web | Community interest |
 
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