Fix: Update Dockerfile to build application from source and adjust Firebase Storage stub return type

Dockerfile

@@ -23,7 +23,9 @@ WORKDIR /app
 COPY package.json package-lock.json ./
 RUN npm ci
 
-COPY build ./build
+COPY . .
+RUN npm run build
+
 COPY public ./public
 COPY licensed ./licensed
 

src/shared/services/firebase-storage-bucket.ts

@@ -5,7 +5,7 @@ export class FirebaseStorageBucketControl {
     return '';
   }
   
-  static async download(path: string): Promise<Buffer | null> {
+  static async download(path: string): Promise<ArrayBuffer | null> {
     // Stub implementation
     return null;
   }