fix!: require NODE_USE_ENV_PROXY for proxy support (#342)

BREAKING CHANGE: Custom proxy handling has been removed. If you use HTTP_PROXY or HTTPS_PROXY, you must now also set NODE_USE_ENV_PROXY=1 on the action step.

README.md

@@ -296,6 +296,24 @@ jobs:
           GITHUB_TOKEN: ${{ steps.create_token.outputs.token }}
 ```
 
+### Proxy support
+
+This action relies on Node.js native proxy support.
+
+If you set `HTTP_PROXY` or `HTTPS_PROXY`, also set `NODE_USE_ENV_PROXY: "1"` on the action step so Node.js honors those variables. If you need proxy bypass rules, set `NO_PROXY` alongside them.
+
+```yaml
+- uses: actions/create-github-app-token@v3
+  id: app-token
+  env:
+    HTTPS_PROXY: http://proxy.example.com:8080
+    NO_PROXY: github.example.com
+    NODE_USE_ENV_PROXY: "1"
+  with:
+    app-id: ${{ vars.APP_ID }}
+    private-key: ${{ secrets.PRIVATE_KEY }}
+```
+
 ## Inputs
 
 ### `app-id`