Add filesystem based blob storage (#3187)

* Refactor transaction hooks. Add preCommit
* Add BlobStore
* Use blobStore for tag images
* Use blobStore for studio images
* Use blobStore for performer images
* Use blobStore for scene covers
* Don't generate screenshots in legacy directory
* Run post-hooks outside original transaction
* Use blobStore for movie images
* Remove unnecessary DestroyImage methods
* Add missing filter for scene cover
* Add covers to generate options
* Add generate cover option to UI
* Add screenshot migration
* Delete thumb files as part of screenshot migration

pkg/sqlite/blob_test.go

@@ -0,0 +1,45 @@
+//go:build integration
+// +build integration
+
+package sqlite_test
+
+import (
+	"context"
+	"fmt"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+type updateImageFunc func(ctx context.Context, id int, image []byte) error
+type getImageFunc func(ctx context.Context, movieID int) ([]byte, error)
+
+func testUpdateImage(t *testing.T, ctx context.Context, id int, updateFn updateImageFunc, getFn getImageFunc) error {
+	image := []byte("image")
+	err := updateFn(ctx, id, image)
+	if err != nil {
+		return fmt.Errorf("Error updating performer image: %s", err.Error())
+	}
+
+	// ensure image set
+	storedImage, err := getFn(ctx, id)
+	if err != nil {
+		return fmt.Errorf("Error getting image: %s", err.Error())
+	}
+	assert.Equal(t, storedImage, image)
+
+	// set nil image
+	err = updateFn(ctx, id, nil)
+	if err != nil {
+		return fmt.Errorf("error setting nil image: %w", err)
+	}
+
+	// ensure image null
+	storedImage, err = getFn(ctx, id)
+	if err != nil {
+		return fmt.Errorf("Error getting image: %s", err.Error())
+	}
+	assert.Nil(t, storedImage)
+
+	return nil
+}