feat: integrate template awareness into AI assistant

- Add template configurations with file structures and conventions
- Update AI route handler to include template context in system messages
- Pass template type through AIChat component
- Add template-specific run commands
- Enhance AI responses with project structure knowledge
- Move hardcoded run commands from navbar/run.tsx to templates/index.ts

This improves the AI's understanding of different project templates (React, Next.js, Streamlit, Vanilla JS) and enables more contextual assistance based on the project type.

frontend/components/editor/navbar/run.tsx

@@ -7,6 +7,7 @@ import { Sandbox } from "@/lib/types"
 import { Play, StopCircle } from "lucide-react"
 import { useEffect, useRef } from "react"
 import { toast } from "sonner"
+import { templateConfigs } from "@/lib/templates"
 
 export default function RunButtonModal({
   isRunning,
@@ -47,8 +48,7 @@ export default function RunButtonModal({
       setIsPreviewCollapsed(true)
       previewPanelRef.current?.collapse()
     } else if (!isRunning && terminals.length < 4) {
-      const command =
-        COMMANDS[sandboxData.type as keyof typeof COMMANDS] ?? COMMANDS.default
+      const command = templateConfigs[sandboxData.type]?.runCommand || "npm run dev"
 
       try {
         // Create a new terminal with the appropriate command