Use pre-built rego-windows image instead of build directive

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Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

apps/rego-tunnel/docker-compose.yml

@@ -1,11 +1,6 @@
-version: '3.9'
-
 services:
   rego-tunnel:
     container_name: rego-tunnel
-    build:
-      context: ./build
-      dockerfile: Dockerfile
     image: rego-windows:latest
     restart: unless-stopped
     devices: