Add findFiles and findFile graphql queries (#5941)

* Add findFile and findFiles
* Add parent folder and zip file fields to file graphql types
* Add parent_folder, zip_file fields to Folder graphql type
* Add format to ImageFile type
* Add format filter fields to image/video file filters

internal/api/fields.go

@@ -0,0 +1,23 @@
+package api
+
+import (
+	"context"
+
+	"github.com/99designs/gqlgen/graphql"
+)
+
+type queryFields []string
+
+func collectQueryFields(ctx context.Context) queryFields {
+	fields := graphql.CollectAllFields(ctx)
+	return queryFields(fields)
+}
+
+func (f queryFields) Has(field string) bool {
+	for _, v := range f {
+		if v == field {
+			return true
+		}
+	}
+	return false
+}