fix: use Node.js wrapper for cross-platform PORT fallback

Replace cross-env with a simple Node.js wrapper script that:
- Respects externally supplied PORT environment variable
- Falls back to 8502 if PORT is not set
- Works cross-platform without extra dependencies
- No runtime dependencies beyond Node.js itself

Changes:
- Add start-server.js wrapper script
- Update package.json to use wrapper
- Remove cross-env dependency
- Copy start-server.js in Dockerfile

This fixes both issues:
1. Preserves PORT fallback behavior (PORT can be overridden)
2. No extra runtime dependencies needed

Dockerfile

@@ -74,6 +74,7 @@ ENV VIRTUAL_ENV=/app/.venv
 COPY --from=builder /app/frontend/.next/standalone /app/frontend/
 COPY --from=builder /app/frontend/.next/static /app/frontend/.next/static
 COPY --from=builder /app/frontend/public /app/frontend/public
+COPY --from=builder /app/frontend/start-server.js /app/frontend/start-server.js
 
 # Expose ports for Frontend and API
 EXPOSE 8502 5055

frontend/package-lock.json

@@ -54,7 +54,6 @@
         "@types/node": "^20",
         "@types/react": "^19",
         "@types/react-dom": "^19",
-        "cross-env": "^10.1.0",
         "eslint": "^9",
         "eslint-config-next": "15.4.2",
         "tailwindcss": "^4",
@@ -126,13 +125,6 @@
         "tslib": "^2.4.0"
       }
     },
-    "node_modules/@epic-web/invariant": {
-      "version": "1.0.0",
-      "resolved": "https://registry.npmjs.org/@epic-web/invariant/-/invariant-1.0.0.tgz",
-      "integrity": "sha512-lrTPqgvfFQtR/eY/qkIzp98OGdNJu0m5ji3q/nJI8v3SXkRKEnWiOxMmbvcSoAIzv/cGiuvRy57k4suKQSAdwA==",
-      "dev": true,
-      "license": "MIT"
-    },
     "node_modules/@eslint-community/eslint-utils": {
       "version": "4.7.0",
       "resolved": "https://registry.npmjs.org/@eslint-community/eslint-utils/-/eslint-utils-4.7.0.tgz",
@@ -4046,24 +4038,6 @@
       "integrity": "sha512-/Srv4dswyQNBfohGpz9o6Yb3Gz3SrUDqBH5rTuhGR7ahtlbYKnVxw2bCFMRljaA7EXHaXZ8wsHdodFvbkhKmqg==",
       "dev": true
     },
-    "node_modules/cross-env": {
-      "version": "10.1.0",
-      "resolved": "https://registry.npmjs.org/cross-env/-/cross-env-10.1.0.tgz",
-      "integrity": "sha512-GsYosgnACZTADcmEyJctkJIoqAhHjttw7RsFrVoJNXbsWWqaq6Ym+7kZjq6mS45O0jij6vtiReppKQEtqWy6Dw==",
-      "dev": true,
-      "license": "MIT",
-      "dependencies": {
-        "@epic-web/invariant": "^1.0.0",
-        "cross-spawn": "^7.0.6"
-      },
-      "bin": {
-        "cross-env": "dist/bin/cross-env.js",
-        "cross-env-shell": "dist/bin/cross-env-shell.js"
-      },
-      "engines": {
-        "node": ">=20"
-      }
-    },
     "node_modules/cross-spawn": {
       "version": "7.0.6",
       "resolved": "https://registry.npmjs.org/cross-spawn/-/cross-spawn-7.0.6.tgz",

frontend/package.json

@@ -5,7 +5,7 @@
   "scripts": {
     "dev": "next dev",
     "build": "next build",
-    "start": "cross-env PORT=8502 node .next/standalone/server.js",
+    "start": "node start-server.js",
     "lint": "next lint"
   },
   "dependencies": {
@@ -55,7 +55,6 @@
     "@types/node": "^20",
     "@types/react": "^19",
     "@types/react-dom": "^19",
-    "cross-env": "^10.1.0",
     "eslint": "^9",
     "eslint-config-next": "15.4.2",
     "tailwindcss": "^4",

frontend/start-server.js

@@ -0,0 +1,9 @@
+#!/usr/bin/env node
+
+// Set default PORT if not already set
+if (!process.env.PORT) {
+  process.env.PORT = '8502';
+}
+
+// Start the Next.js standalone server
+require('./.next/standalone/server.js');