[docs] Update documentation for features from 2026-07-26

docs/src/content/docs/reference/safe-outputs.md

@@ -1631,6 +1631,24 @@ safe-outputs:
     github-token: ${{ secrets.PR_PAT }}    # per-output
 ```
 
+`github-token` accepts these GitHub Actions expression forms:
+
+- `secrets.NAME`
+- `needs.<job>.outputs.<name>`
+- `steps.<id>.outputs.<name>`
+
+The `steps.*.outputs.*` form is useful when the safe-outputs job mints a short-lived token in `pre-steps:` or `setup-steps:` and then reuses that token for `Process Safe Outputs` in the same job.
+
+```yaml wrap
+pre-steps:
+  - id: fetch_token
+    run: echo "token=${TOKEN}" >> "$GITHUB_OUTPUT"
+
+safe-outputs:
+  github-token: ${{ steps.fetch_token.outputs.token }}
+  create-pull-request:
+```
+
 ### Using a GitHub App for Authentication (`github-app:`)
 
 Use GitHub App tokens for enhanced security: on-demand token minting, automatic revocation, fine-grained permissions, and better attribution.

docs/src/content/docs/reference/sandbox.md

@@ -145,6 +145,28 @@ jobs:
 Use `go build` or `python3` - both are available.
 ```
 
+#### Copilot BYOK request customization (`sandbox.agent.targets.copilot`)
+
+When routing Copilot through a BYOK-compatible upstream behind the AWF proxy, you can attach custom headers, extra request body fields, and an explicit session identifier on upstream requests:
+
+```yaml wrap
+sandbox:
+  agent:
+    targets:
+      copilot:
+        extraHeaders:
+          x-openrouter-title: my-workflow
+          http-referer: https://github.com/${{ github.repository }}
+        extraBodyFields:
+          custom-field: custom-value
+        sessionId: ${{ github.run_id }}
+```
+
+Use this for OpenAI-compatible proxies and gateways that expect additional request metadata. `sessionId` is opt-in only; gh-aw does not derive it automatically.
+
+> [!NOTE]
+> Set `sessionId` only when your upstream expects a session identifier. Some strict OpenAI-compatible providers reject unknown `session_id` fields, so automatic injection would be unsafe.
+
 #### Go cache paths in AWF (`GOMODCACHE` / `GOCACHE`)
 
 When using `actions/setup-go` in AWF, pin Go cache paths explicitly so restore behavior is predictable: