feat: image variants cache panel

internal/domain/image/variantRepositoryInterface.go

@@ -1,6 +1,9 @@
 package image
 
-import "io"
+import (
+	"io"
+	"time"
+)
 
 type VariantRepository interface {
 	List() ([]Variant, error)
@@ -20,6 +23,23 @@ type VariantFileRepository interface {
 	TotalsBySource() (map[string]VariantFileTotals, error)
 }
 
+type VariantCacheRepository interface {
+	UnusedTotals(filter UnusedFilter) (VariantFileTotals, error)
+	TopSources(limit int) ([]SourceTotals, error)
+	ListPage(filter VariantFileFilter, afterID uint32, limit int) ([]VariantFile, error)
+}
+
+type VariantUsageRepository interface {
+	Record(batch VariantUsageBatch) error
+	RejectedSince(day time.Time) (int, error)
+}
+
+type VariantUsageTracker interface {
+	RecordHit(variantName string, sourceName string)
+	RecordRejection()
+	Flush() error
+}
+
 type RenderedVariant struct {
 	Content     []byte
 	ContentType string