feat(version): answer the build commit and time

GET /api/version is public. CI passes GIT_SHA and BUILD_TIME as Docker build args; a local build answers dev.

.gitea/workflows/publish-core.yml

@@ -52,6 +52,7 @@ jobs:
           BRANCH="$(echo "$BRANCH" | tr '[:upper:]' '[:lower:]')"
           echo "branch=$BRANCH" >> "$GITHUB_OUTPUT"
           echo "sha=${GITHUB_SHA::12}" >> "$GITHUB_OUTPUT"
+          echo "build_time=$(date -u +%Y-%m-%dT%H:%M:%SZ)" >> "$GITHUB_OUTPUT"
 
       - name: Set up Docker Buildx
         uses: docker/setup-buildx-action@v3
@@ -69,6 +70,9 @@ jobs:
         with:
           context: .
           push: true
+          build-args: |
+            GIT_SHA=${{ github.sha }}
+            BUILD_TIME=${{ steps.prep.outputs.build_time }}
           tags: |
             git.andreas-dahm.eu/lobo_corp/tbp-core-service:${{ steps.prep.outputs.branch }}
             git.andreas-dahm.eu/lobo_corp/tbp-core-service:${{ steps.prep.outputs.branch }}-${{ steps.prep.outputs.sha }}