init: kovakemlak-crm project scaffold

- Next.js 16 + Appwrite multi-tenant emlak CRM
- Database: kovakemlak-db (properties, customers, customer_searches, property_matches, presentations, investors, activities, tenant_settings)
- Same stack as isletmem-kovakcrm (shadcn/ui template base)
- Modules: portföy, müşteri takibi, arama kriterleri, otomatik eşleştirme, sunum linki, yatırımcı portalı

src/hooks/use-fullscreen.ts

@@ -0,0 +1,49 @@
+"use client"
+
+import { useState, useEffect } from "react"
+
+export function useFullscreen() {
+  const [isFullscreen, setIsFullscreen] = useState(false)
+
+  useEffect(() => {
+    const handleFullscreenChange = () => {
+      setIsFullscreen(!!document.fullscreenElement)
+    }
+
+    document.addEventListener("fullscreenchange", handleFullscreenChange)
+    
+    // Initial check
+    setIsFullscreen(!!document.fullscreenElement)
+
+    return () => {
+      document.removeEventListener("fullscreenchange", handleFullscreenChange)
+    }
+  }, [])
+
+  const enterFullscreen = () => {
+    if (!document.fullscreenElement) {
+      document.documentElement.requestFullscreen().catch(console.error)
+    }
+  }
+
+  const exitFullscreen = () => {
+    if (document.fullscreenElement) {
+      document.exitFullscreen().catch(console.error)
+    }
+  }
+
+  const toggleFullscreen = () => {
+    if (isFullscreen) {
+      exitFullscreen()
+    } else {
+      enterFullscreen()
+    }
+  }
+
+  return {
+    isFullscreen,
+    enterFullscreen,
+    exitFullscreen,
+    toggleFullscreen,
+  }
+}