proxy through varnish

sets up varnish cache server with:
- custom cache per content type
- gzip
- configure app & hass backends
- varnish debug headers & X-Cache verbose cache header

also updates docker-compose, varnish/Dockerfile & drone.

vite.config.ts

@@ -4,11 +4,6 @@ import { defineConfig } from 'vite';
 export default defineConfig({
 	plugins: [sveltekit()],
 	server: {
-		proxy: {
-			'/proxmox': {
-				target: 'https://apollo.schleppe:8006/api2/json',
-				secure: false
-			}
-		}
+		allowedHosts: ['host.docker.internal']
 	}
 });