feat(source2): push all latest files - device labeling, help system, proxy docs, database isolation fix

- Added DOKUMENTASI-FILTER-PER-SITE.md (site isolation docs)
- Fixed start-with-env.js to force-load .env.production
- Fixed MONGODB_URI hostname from mongodb-netify to mongodb.prod.proit.id
- Updated .gitignore to exclude sensitive scripts and credential files
- Minor UI and labeling improvements

backend/Dockerfile.bun

@@ -0,0 +1,15 @@
+FROM oven/bun:1-alpine
+
+WORKDIR /app
+
+COPY backend/package*.json ./
+RUN bun install --production
+
+COPY backend/ .
+
+EXPOSE 3001
+
+HEALTHCHECK --interval=30s --timeout=10s --start-period=20s --retries=3 \
+  CMD bun -e "require('http').get('http://localhost:3001/api/health', r => r.statusCode === 200 ? process.exit(0) : process.exit(1)).on('error', () => process.exit(1))"
+
+CMD ["bun", "run", "server.js"]