fix(docs): redirect integration sections to source

[lyydsheep]

Fixes #3752.

Integration sections that contain a source.md page now redirect their root URL to that source page. This applies globally through the shared Hugo section layout, so new integrations inherit the behavior automatically.

Validation:

• Verified the Hugo template references the child source page and emits both a meta refresh and JavaScript fallback.
• git diff --check passes.

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[gemini-code-assist]

Code Review

This pull request introduces an automatic redirect for integration section pages to their corresponding "source" subpage within ".hugo/layouts/docs/section.html". The reviewer identified a potential Hugo build failure (nil pointer evaluation) that can occur if any page in ".Pages" does not have a physical file (where ".File" is nil). They provided a safer implementation that iterates through the pages, verifies ".File" is present, and avoids redundant index lookups.

[gemini-code-assist]

Using where .Pages "File.BaseFileName" "source" can cause a Hugo build failure (nil pointer evaluation) if any page in .Pages does not have a physical file (i.e., .File is nil), which is common for virtual or auto-generated section pages.

Additionally, storing the matched page in a variable avoids repeating index $sourcePages 0 multiple times. We can safely find the source page by iterating and checking if .File is present.

{{ $sourcePage := "" }}
{{ range .Pages }}
  {{ if and .File (eq .File.BaseFileName "source") }}
    {{ $sourcePage = . }}
  {{ end }}
{{ end }}
{{ if and (hasPrefix .RelPermalink "/integrations/") $sourcePage }}
<meta http-equiv="refresh" content="0; url={{ $sourcePage.RelPermalink }}">
<script>window.location.replace({{ $sourcePage.RelPermalink | jsonify }});</script>
<p>Redirecting to <a href="{{ $sourcePage.RelPermalink }}">{{ $sourcePage.Title }}</a>...</p>
{{ else }}

[github-actions]

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[Yuan325]

Hi @lyydsheep thank you for your contribution. I was testing the /integrations/alloydb/ path but seems like it's still showing a blank page.