fix(ci): repair failing Gitea Actions

.gitea/workflows/build-docs.yaml

@@ -21,32 +21,38 @@ jobs:
         with:
           path: api-company
 
+      # NOTE: cross-repo checkouts use SIBLING_REPOS_TOKEN, NOT the auto-injected
+      # GITEA_TOKEN. Gitea's automatic GITEA_TOKEN is scoped to THIS repo only,
+      # so checking out other repos fails with
+      # "Determining the default branch → not found". GITEA_TOKEN is also a
+      # reserved secret name that cannot be overridden, hence a separate secret.
+      # SIBLING_REPOS_TOKEN must be a PAT with read access to the API repos.
       - name: Checkout zip-enrichment
         uses: actions/checkout@v4
         with:
           repository: leeworks-agents/zip-enrichment
-          token: ${{ secrets.GITEA_TOKEN }}
+          token: ${{ secrets.SIBLING_REPOS_TOKEN }}
           path: zip-enrichment
 
       - name: Checkout holidays
         uses: actions/checkout@v4
         with:
           repository: leeworks-agents/holidays
-          token: ${{ secrets.GITEA_TOKEN }}
+          token: ${{ secrets.SIBLING_REPOS_TOKEN }}
           path: holidays
 
       - name: Checkout air-quality
         uses: actions/checkout@v4
         with:
           repository: leeworks-agents/air-quality
-          token: ${{ secrets.GITEA_TOKEN }}
+          token: ${{ secrets.SIBLING_REPOS_TOKEN }}
           path: air-quality
 
       - name: Checkout vin-decoder
         uses: actions/checkout@v4
         with:
           repository: leeworks-agents/vin-decoder
-          token: ${{ secrets.GITEA_TOKEN }}
+          token: ${{ secrets.SIBLING_REPOS_TOKEN }}
           path: vin-decoder
 
       - name: Copy openapi.yaml specs into docs-site