feat(quick-5): add CreatedAt/UpdatedAt to playlist Summary struct

- Add CreatedAt and UpdatedAt string fields to Summary struct
- Format as RFC3339 at all construction sites in playlist.go and favorites.go
- Update TypeScript bindings with new fields in models.ts

frontend/wailsjs/go/models.ts

@@ -305,6 +305,8 @@ export namespace playlist {
 	export class Summary {
 	    ID: number;
 	    Name: string;
+	    CreatedAt: string;
+	    UpdatedAt: string;
 	
 	    static createFrom(source: any = {}) {
 	        return new Summary(source);
@@ -314,6 +316,8 @@ export namespace playlist {
 	        if ('string' === typeof source) source = JSON.parse(source);
 	        this.ID = source["ID"];
 	        this.Name = source["Name"];
+	        this.CreatedAt = source["CreatedAt"];
+	        this.UpdatedAt = source["UpdatedAt"];
 	    }
 	}
 	export class Track {