Fix: Use npm install instead of npm ci to avoid lock file requirement

Dockerfile

@@ -8,7 +8,7 @@ WORKDIR /app/client
 COPY client/package*.json ./
 
 # Install frontend dependencies
-RUN npm ci --production=false
+RUN npm install
 
 # Copy frontend source
 COPY client/ ./
@@ -31,8 +31,8 @@ WORKDIR /app
 # Copy root package files
 COPY package*.json ./
 
-# Install production dependencies only
-RUN npm ci --production
+# Install production dependencies
+RUN npm install --omit=dev
 
 # Copy server code
 COPY server/ ./server/