Fix Portainer deploy: use variable substitution instead of env_file

docker-compose.yml

@@ -12,8 +12,16 @@ services:
     restart: unless-stopped
     ports:
       - "5173:5173"
-    env_file:
-      - .env
+    environment:
+      - MOCK_AI=${MOCK_AI:-false}
+      - ANTHROPIC_API_KEY=${ANTHROPIC_API_KEY:-}
+      - APP_USERS=${APP_USERS:-}
+      - APP_USERNAME=${APP_USERNAME:-}
+      - APP_PASSWORD=${APP_PASSWORD:-}
+      - RATE_LIMIT_MAX=${RATE_LIMIT_MAX:-20}
+      - RATE_LIMIT_WINDOW_MS=${RATE_LIMIT_WINDOW_MS:-300000}
+      - TOKEN_LIMIT_PER_USER=${TOKEN_LIMIT_PER_USER:-0}
+      - TOKEN_USAGE_FILE=${TOKEN_USAGE_FILE:-./data/token-usage.json}
     volumes:
       # Persists the per-user token quota file across restarts and rebuilds.
       # Without this, everyone's daily usage silently resets on every deploy.