feat: setup frontend project with bun and dynamic data fetching

- Create new frontend project directory with Next.js 15 + React 19
- Migrate from pnpm to bun for faster package management
- Add TanStack Query + Axios for dynamic data fetching
- Create comprehensive Makefile with development commands
- Setup API layer with query hooks and error handling
- Configure environment variables and bun settings
- Add TypeScript type checking and project documentation
- Update CLAUDE.md with bun-specific development workflow

frontend/hooks/use-mobile.tsx

@@ -0,0 +1,19 @@
+import * as React from "react"
+
+const MOBILE_BREAKPOINT = 768
+
+export function useIsMobile() {
+  const [isMobile, setIsMobile] = React.useState<boolean | undefined>(undefined)
+
+  React.useEffect(() => {
+    const mql = window.matchMedia(`(max-width: ${MOBILE_BREAKPOINT - 1}px)`)
+    const onChange = () => {
+      setIsMobile(window.innerWidth < MOBILE_BREAKPOINT)
+    }
+    mql.addEventListener("change", onChange)
+    setIsMobile(window.innerWidth < MOBILE_BREAKPOINT)
+    return () => mql.removeEventListener("change", onChange)
+  }, [])
+
+  return !!isMobile
+}