Fix missing images on PR preview deployments

[brooke-hamilton]

Problem

Azure Static Web Apps PR-preview deployments render all images blank (0×0). The CI workflow baked a guessed preview hostname into Hugo's baseURL:

STAGING_URL="https://${SWA_BASE}-${{github.event.number}}.3.azurestaticapps.net/"
hugo ${STAGING_URL+-b "$STAGING_URL"}

This produced e.g. https://brave-pond-00b49761e-59.3.azurestaticapps.net/, which the theme emits as <base href="{{ site.BaseURL }}"> (themes/bigspring-light/layouts/partials/head.html).

But Azure actually serves the preview from a region-qualified host like https://brave-pond-00b49761e-59.westus2.3.azurestaticapps.net/. Because the <base href> host differs from the host actually serving the page, every relative asset URL (e.g. /images/...) resolves cross-origin. Chrome blocks those requests with ERR_BLOCKED_BY_ORB, so images render blank.

Fix

For pull_request builds, stop guessing the preview hostname and build with a root-relative baseURL so <base href="/"> resolves against whatever host actually serves the page:

- name: Build Hugo Site
  run: |
    if [ "${GITHUB_EVENT_NAME}" == 'pull_request' ]; then
      hugo -b "/"
    else
      hugo
    fi

The now-unused SWA_BASE env var was removed (it was only referenced by the old step).

Why production is unaffected

Production builds (push to main) take the else branch and use the repo's configured baseURL (https://radapp.io/), which already matches its serving domain. Only the preview branch behavior changes.

[github-actions]

Dependency Review

✅ No vulnerabilities or license issues or OpenSSF Scorecard issues found.

Scanned Files

None

[Copilot]

Pull request overview

This PR fixes broken image rendering in Azure Static Web Apps PR-preview deployments by avoiding a guessed preview hostname in Hugo’s baseURL. For pull_request events, the workflow now builds the site with a root-relative base URL so the theme’s <base href="{{ site.BaseURL }}"> resolves assets against the actual preview host being served.

Changes:

• Remove the unused SWA_BASE environment variable from the workflow.
• For pull_request builds, run hugo -b "/" instead of constructing a preview hostname.
• Keep production (push to main) builds unchanged by continuing to run hugo with the configured repository baseURL.

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