Fix wait-on-check-action ref mismatch (#14)

* Initial plan

* Fix wait-on-check-action ref and check-name configuration

Co-authored-by: PhantomDave <34485699+PhantomDave@users.noreply.github.com>

* Fix frontend check-name to match container build workflow

Co-authored-by: PhantomDave <34485699+PhantomDave@users.noreply.github.com>

---------

Co-authored-by: copilot-swe-agent[bot] <198982749+Copilot@users.noreply.github.com>
Co-authored-by: PhantomDave <34485699+PhantomDave@users.noreply.github.com>

Author: Copilot

.github/workflows/deploy-tailscale.yml

@@ -49,7 +49,7 @@ jobs:
       - name: Wait for backend image build
         uses: lewagon/wait-on-check-action@v1.3.4
         with:
-          ref: ${{ github.ref }}
+          ref: ${{ github.sha }}
           check-name: 'Build and Push Backend Container'
           repo-token: ${{ secrets.GITHUB_TOKEN }}
           wait-interval: 10
@@ -65,7 +65,7 @@ jobs:
       - name: Wait for frontend image build
         uses: lewagon/wait-on-check-action@v1.3.4
         with:
-          ref: ${{ github.ref }}
+          ref: ${{ github.sha }}
           check-name: 'Build and Push Frontend Container'
           repo-token: ${{ secrets.GITHUB_TOKEN }}
           wait-interval: 10