Fix Docker deployment and runtime environment variables

- Add --break-system-packages flag to pip install for Alpine Linux 3.12+ compatibility
- Configure Astro server to bind to 0.0.0.0 for Docker container accessibility
- Replace import.meta.env with process.env for runtime environment variable access in SSR
- Enable dynamic LOGIN configuration at runtime

Co-Authored-By: Warp <agent@warp.dev>

src/pages/api/download.ts

@@ -48,7 +48,7 @@ export const POST: APIRoute = async ({ request }) => {
     }
 
     // Prüfe ob Stream-Modus aktiviert ist
-    const streamOnly = import.meta.env.STREAM_ONLY === "true";
+    const streamOnly = process.env.STREAM_ONLY === "true";
 
     // yt-dlp-wrap Instanz erstellen
     const ytDlpWrap = new YTDlpWrap();
@@ -154,7 +154,7 @@ export const POST: APIRoute = async ({ request }) => {
     } else {
       // NORMALER MODUS: Datei speichern wie bisher
       const downloadDir =
-        import.meta.env.DOWNLOAD_DIR || path.join(process.cwd(), "downloaded");
+        process.env.DOWNLOAD_DIR || path.join(process.cwd(), "downloaded");
 
       // Verzeichnis erstellen falls nicht vorhanden
       try {