fix: use --load --output=type=docker for local builds so images are available to run

.gitea/actions/docker-build/action.yml

@@ -108,7 +108,6 @@ runs:
       env:
         DOCKER_BUILDKIT: "1"
       run: |
-        set -x
         CACHE_FROM_FLAG=""
         if [ -n "${{ inputs.cache-from }}" ]; then
           CACHE_FROM_FLAG="--cache-from=${{ inputs.cache-from }}"
@@ -126,11 +125,14 @@ runs:
           PLATFORM_FLAG="--platform=${{ inputs.platforms }}"
         fi
 
-        PUSH_FLAG=""
+        # Choose output mode
         if [ "${{ inputs.push }}" = "true" ]; then
-          PUSH_FLAG="--push"
+          OUTPUT_FLAG="--push --output=type=registry"
+        else
+          OUTPUT_FLAG="--load --output=type=docker"
         fi
 
+        set -x
         docker buildx build \
           $PLATFORM_FLAG \
           --tag "${{ inputs.image-name }}:${{ steps.meta.outputs.tag }}" \
@@ -141,7 +143,7 @@ runs:
           $CACHE_FROM_FLAG \
           $BUILD_ARGS_FLAG \
           --progress=plain \
-          $PUSH_FLAG \
+          $OUTPUT_FLAG \
           ${{ inputs.context }}
 
     - name: Get image digest