Gluetun: pass full single-peer WireGuard config to the container

The compose only forwarded VPN_SERVICE_PROVIDER, VPN_TYPE and the private
key, so Gluetun could not form a tunnel. Forward the peer public key,
endpoint IP/port, addresses, allowed IPs and keepalive interval. Add
matching placeholders to .env.example (current Gluetun uses the
single-peer WIREGUARD_* model, not the old WIREGUARD_PEERS_* names).

dankclaw/.env.example

@@ -6,9 +6,16 @@ SEARXNG_SECRET=changeme
 SEARXNG_BASE_URL=http://search.dankclaw.local/
 
 # Gluetun VPN (see https://github.com/qdm12/gluetun-wiki)
-VPN_SERVICE_PROVIDER=mullvad
+# Single-peer WireGuard model. Fill from your provider's WireGuard config.
+VPN_SERVICE_PROVIDER=protonvpn
 VPN_TYPE=wireguard
 WIREGUARD_PRIVATE_KEY=changeme
+WIREGUARD_ADDRESSES=0.0.0.0/32
+WIREGUARD_PUBLIC_KEY=changeme
+WIREGUARD_ENDPOINT_IP=0.0.0.0
+WIREGUARD_ENDPOINT_PORT=51820
+WIREGUARD_ALLOWED_IPS=0.0.0.0/0,::/0
+WIREGUARD_PERSISTENT_KEEPALIVE_INTERVAL=25s
 
 # Gitea database
 GITEA_DB_PASSWORD=changeme