fix: Use npm install in builder stage (not npm ci)

- Changed builder stage from 'npm ci' to 'npm install'
- Production stage already uses 'npm install --production'
- Both stages now forgiving with cached package files
- Fixes Easypanel build cache issues completely

Dockerfile

@@ -4,7 +4,7 @@ FROM node:20-alpine AS builder
 WORKDIR /app
 
 COPY package*.json ./
-RUN npm ci
+RUN npm install
 
 COPY . .