feat: Customizable shortcuts/hotkeys (#439)

This implements the logic for allowing hotkeys with modifiers.
Implemented globalhotkeys and videocontrol hotkeys
Also implements saving the forward backwards seconds to the user.

Co-authored-by: PartyDonut <PartyDonut@users.noreply.github.com>

lib/models/settings/key_combinations.freezed.dart

@@ -0,0 +1,79 @@
+// coverage:ignore-file
+// GENERATED CODE - DO NOT MODIFY BY HAND
+// ignore_for_file: type=lint
+// ignore_for_file: unused_element, deprecated_member_use, deprecated_member_use_from_same_package, use_function_type_syntax_for_parameters, unnecessary_const, avoid_init_to_null, invalid_override_different_default_values_named, prefer_expression_function_bodies, annotate_overrides, invalid_annotation_target, unnecessary_question_mark
+
+part of 'key_combinations.dart';
+
+// **************************************************************************
+// FreezedGenerator
+// **************************************************************************
+
+T _$identity<T>(T value) => value;
+
+final _privateConstructorUsedError = UnsupportedError(
+    'It seems like you constructed your class using `MyClass._()`. This constructor is only meant to be used by freezed and you are not supposed to need it nor use it.\nPlease check the documentation here for more information: https://github.com/rrousselGit/freezed#adding-getters-and-methods-to-our-models');
+
+KeyCombination _$KeyCombinationFromJson(Map<String, dynamic> json) {
+  return _KeyCombination.fromJson(json);
+}
+
+/// @nodoc
+mixin _$KeyCombination {
+  @LogicalKeyboardSerializer()
+  LogicalKeyboardKey? get modifier => throw _privateConstructorUsedError;
+  @LogicalKeyboardSerializer()
+  LogicalKeyboardKey get key => throw _privateConstructorUsedError;
+
+  /// Serializes this KeyCombination to a JSON map.
+  Map<String, dynamic> toJson() => throw _privateConstructorUsedError;
+}
+
+/// @nodoc
+@JsonSerializable()
+class _$KeyCombinationImpl extends _KeyCombination {
+  _$KeyCombinationImpl(
+      {@LogicalKeyboardSerializer() this.modifier,
+      @LogicalKeyboardSerializer() required this.key})
+      : super._();
+
+  factory _$KeyCombinationImpl.fromJson(Map<String, dynamic> json) =>
+      _$$KeyCombinationImplFromJson(json);
+
+  @override
+  @LogicalKeyboardSerializer()
+  final LogicalKeyboardKey? modifier;
+  @override
+  @LogicalKeyboardSerializer()
+  final LogicalKeyboardKey key;
+
+  @override
+  String toString() {
+    return 'KeyCombination(modifier: $modifier, key: $key)';
+  }
+
+  @override
+  Map<String, dynamic> toJson() {
+    return _$$KeyCombinationImplToJson(
+      this,
+    );
+  }
+}
+
+abstract class _KeyCombination extends KeyCombination {
+  factory _KeyCombination(
+          {@LogicalKeyboardSerializer() final LogicalKeyboardKey? modifier,
+          @LogicalKeyboardSerializer() required final LogicalKeyboardKey key}) =
+      _$KeyCombinationImpl;
+  _KeyCombination._() : super._();
+
+  factory _KeyCombination.fromJson(Map<String, dynamic> json) =
+      _$KeyCombinationImpl.fromJson;
+
+  @override
+  @LogicalKeyboardSerializer()
+  LogicalKeyboardKey? get modifier;
+  @override
+  @LogicalKeyboardSerializer()
+  LogicalKeyboardKey get key;
+}