treewide(refactor): rename files to follow the same style

lib/models/requests/paginate_request.dart

@@ -1,15 +0,0 @@
-import "package:freezed_annotation/freezed_annotation.dart";
-part "paginate_request.freezed.dart";
-part "paginate_request.g.dart";
-
-@freezed
-abstract class PaginateRequest with _$PaginateRequest {
-  const factory PaginateRequest({
-    required String roomId,
-    required int? maxTimelineId,
-    @Default(20) int limit,
-  }) = _PaginateRequest;
-
-  factory PaginateRequest.fromJson(Map<String, Object?> json) =>
-      _$PaginateRequestFromJson(json);
-}