fix: resolve terraform-docs workflow git push failure

- Add conditional checkout ref for pull_request vs push events
- Use github.head_ref for PRs to avoid detached HEAD state
- Add push trigger for main branch commits
- Include GITHUB_TOKEN for proper authentication

This fixes the CI failure where terraform-docs couldn't push
changes from detached HEAD state in PR contexts.

🤖 Generated with [Claude Code](https://claude.ai/code)

Co-Authored-By: Claude <[email protected]>

Author: vjdhama

.github/workflows/terraform-docs.yaml

@@ -1,7 +1,10 @@
 name: Terraform Docs
 
 on:
-  workflow_call:
+  pull_request:
+  push:
+    branches:
+      - main
 
 env:
   TERRAFORM_DOCS_VERSION: v0.18.0
@@ -13,7 +16,8 @@ jobs:
       - name: Checkout repository
         uses: actions/checkout@v4
         with:
-          ref: ${{ github.ref }}
+          ref: ${{ github.event_name == 'pull_request' && github.head_ref || github.ref }}
+          token: ${{ secrets.GITHUB_TOKEN }}
 
       - name: Render and Push terraform docs for main module
         uses: terraform-docs/gh-actions@main