docs(zai): align setup guide with runtime defaults

- remove trailing whitespace in .env.example Z.AI block
- align documented model defaults/options with current onboard/provider behavior
- keep this PR docs-focused by reverting incidental workflow edits

.github/workflows/pr-auto-response.yml

@@ -40,8 +40,8 @@ jobs:
       - name: Greet first-time contributors
         uses: actions/first-interaction@a1db7729b356323c7988c20ed6f0d33fe31297be # v1
         with:
-          repo_token: ${{ secrets.GITHUB_TOKEN }}
-          issue_message: |
+          repo-token: ${{ secrets.GITHUB_TOKEN }}
+          issue-message: |
             Thanks for opening this issue.
 
             Before maintainers triage it, please confirm:
@@ -50,7 +50,7 @@ jobs:
             - Sensitive values are redacted
 
             This helps us keep issue throughput high and response latency low.
-          pr_message: |
+          pr-message: |
             Thanks for contributing to ZeroClaw.
 
             For faster review, please ensure: