feat: support outbound proxy for Chromium sessions (#131)

* feat: support outbound proxy for Chromium sessions

Routes WhatsApp Web traffic through an HTTP/HTTPS/SOCKS5 proxy when
PROXY_URL is set. Optional PROXY_API_KEY enables auth by passing the
key as the basic-auth username (the format API-key proxies expect).
No behavior change when unset.

Useful for deployments behind egress filters or where outbound
WhatsApp traffic must originate from a specific IP.

* docs: 📝 rewrite proxy auth part

* fix: 🐛 move api key value to passwd

* fix: 💄 change var naming

* fix: 🎨 change var ref in docs and data passing

docker-compose.yml

@@ -13,6 +13,16 @@ services:
     env_file: .env
     volumes:
       - ./sessions:/usr/src/app/sessions
+    # Optional: route Chromium (WhatsApp Web) traffic through an outbound proxy.
+    # Set PROXY_URL (and optionally PROXY_USERNAME / PROXY_PASSWORD for HTTP
+    # Basic auth) in .env, or uncomment the block below to point at the
+    # bundled tinyproxy service.
+    # environment:
+    #   PROXY_URL: http://tinyproxy:8888
+    #   # PROXY_USERNAME: api-key
+    #   # PROXY_PASSWORD: your-api-key
+    # depends_on:
+    #   - tinyproxy
     # Optional healthcheck
     # healthcheck:
     #   test: ["CMD", "curl", "-f", "http://localhost:3000/health"]
@@ -20,3 +30,17 @@ services:
     #   timeout: 10s
     #   retries: 3
     #   start_period: 40s
+
+  # Optional: local HTTP proxy for testing the PROXY_URL feature end-to-end.
+  # Uncomment along with the api `environment` / `depends_on` blocks above.
+  # tinyproxy:
+  #   image: vimagick/tinyproxy
+  #   container_name: wwebjs-tinyproxy
+  #   ports:
+  #     - "8888:8888"
+  #   environment:
+  #     ALLOWED_NETWORKS: 0.0.0.0/0
+  #     # Uncomment to test the PROXY_USERNAME / PROXY_PASSWORD path.
+  #     # BASIC_AUTH_USER: "api-key"
+  #     # BASIC_AUTH_PASSWORD: "your-api-key"
+  #   restart: unless-stopped