Fix: Define NEXT_PUBLIC variables explicitly in Dockerfile for build time

Added explicit ENV declarations for all NEXT_PUBLIC_* variables in the
builder stage before npm run build. This ensures Next.js correctly bakes
these values into the JavaScript bundle, regardless of lionsctl's
automatic manifest generation.

Variables defined:
- NEXT_PUBLIC_API_URL=https://api.lions.dev/btpxpress
- NEXT_PUBLIC_KEYCLOAK_URL=https://security.lions.dev
- NEXT_PUBLIC_KEYCLOAK_REALM=btpxpress
- NEXT_PUBLIC_KEYCLOAK_CLIENT_ID=btpxpress-frontend
- NEXT_PUBLIC_APP_ENV=production

This fixes the issue where the frontend was using https://api.lions.dev
instead of https://api.lions.dev/btpxpress for API calls.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <noreply@anthropic.com>

Dockerfile

@@ -22,6 +22,14 @@ COPY . .
 # Build Next.js application
 ENV NODE_ENV production
 ENV NEXT_TELEMETRY_DISABLED 1
+
+# Define NEXT_PUBLIC variables explicitly for build time
+ENV NEXT_PUBLIC_API_URL=https://api.lions.dev/btpxpress
+ENV NEXT_PUBLIC_KEYCLOAK_URL=https://security.lions.dev
+ENV NEXT_PUBLIC_KEYCLOAK_REALM=btpxpress
+ENV NEXT_PUBLIC_KEYCLOAK_CLIENT_ID=btpxpress-frontend
+ENV NEXT_PUBLIC_APP_ENV=production
+
 RUN npm run build
 
 ## Stage 3: Production image