Fix stage source check: run after checkout, not before

git log -1 fails with 'not a git repository' when the workspace
hasn't been checked out yet. Move the Enforce dev-only source step
to after the Checkout step.

.gitea/workflows/stage.yaml

@@ -32,10 +32,16 @@ jobs:
       id-token: write
 
     steps:
+      - name: Checkout
+        uses: actions/checkout@v4
+        with:
+          fetch-depth: 2
+
       - name: Enforce dev-only source
         # stage only accepts merges from dev. Any PR from another branch fails
         # here before a single build step runs.
         # workflow_dispatch is exempt (allows manual redeploy of current stage).
+        # Must run AFTER checkout — git commands require a cloned workspace.
         if: github.event_name != 'workflow_dispatch'
         run: |
           set -euo pipefail
@@ -61,11 +67,6 @@ jobs:
             exit 1
           fi
 
-      - name: Checkout
-        uses: actions/checkout@v4
-        with:
-          fetch-depth: 2
-
       - name: Detect change type
         id: changetype
         run: |