Add standalone API proxy via curl (bypasses WAF TLS fingerprinting)

Modern.js SSR intercepts all routes before any Express middleware,
so the API proxy runs as a separate Express server on port 8080.
Modern.js runs on 8081. The proxy uses curl subprocesses which go
through the system HTTPS proxy (GOST) with a proper TLS fingerprint
that the Aeroflot WAF accepts.

Usage: node scripts/dev-server.mjs (replaces pnpm dev for full-stack)

Also: remove stray e2e-angular test directory, fix env default to
same-origin /api.

package.json

@@ -23,7 +23,7 @@
     "check-coverage": "node scripts/ci/check-coverage-delta.mjs",
     "test:e2e": "playwright test",
     "proxy": "node scripts/api-proxy.mjs",
-    "dev:full": "node scripts/api-proxy.mjs & pnpm dev"
+    "dev:full": "node scripts/dev-server.mjs"
   },
   "dependencies": {
     "@microsoft/signalr": "^10.0.0",
@@ -68,8 +68,10 @@
     "eslint": "^9.0.0",
     "eslint-plugin-boundaries": "^5.0.0",
     "eslint-plugin-unused-imports": "^4.0.0",
+    "express": "^5.2.1",
     "fast-check": "^4.6.0",
     "http-proxy-middleware": "^3.0.5",
+    "https-proxy-agent": "^9.0.0",
     "jsdom": "^29.0.2",
     "react-test-renderer": "^19.2.5",
     "sass": "^1.99.0",