fix: use environment substitution instead of env_file for Portainer git deploy

Portainer git deployments have no .env file on disk. Switch to
environment: with ${VAR} substitution — vars injected via Portainer UI.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

docker-compose.yml

@@ -4,7 +4,20 @@ services:
     restart: unless-stopped
     ports:
       - "${PORT:-3001}:3001"
-    env_file: .env
+    environment:
+      - SOLEM_EMAIL=${SOLEM_EMAIL}
+      - SOLEM_PASSWORD=${SOLEM_PASSWORD}
+      - SOLEM_BASE=${SOLEM_BASE:-https://qualif.mysolem.com}
+      - INDYGO_BASE=${INDYGO_BASE:-https://qualif.myindygo.com}
+      - SOLEM_USER_ID=${SOLEM_USER_ID:-5de53bca7ed4c45c2cfe067f}
+      - MQTT_URL=${MQTT_URL}
+      - MQTT_USERNAME=${MQTT_USERNAME}
+      - MQTT_PASSWORD=${MQTT_PASSWORD}
+      - MQTT_TOPIC_PREFIX=${MQTT_TOPIC_PREFIX:-myprimal}
+      - PORT=${PORT:-3001}
+      - POLL_FAST=${POLL_FAST:-60}
+      - POLL_NORMAL=${POLL_NORMAL:-300}
+      - POLL_SLOW=${POLL_SLOW:-900}
     volumes:
       - myprimal-config:/app/config.json