Add home option to VideoFeedInputGQL

The home feed option enables smart feed selection on the backend:
- If user has following: returns FOLLOWING feed
- If user has no following: returns ALL feed
- Always includes hasFollowing flag so frontend knows which feed it got

This allows frontend to make a single query instead of needing to
check following status separately.

src/schema.gql

@@ -28,6 +28,12 @@ type Query {
     when: DateTime = null
   ): CountLeaderboardGQL!
   getMedals(scope: MedalScope!, userId: Int = null): RequestedMedalsGQL!
+  notifications(
+    limit: Int! = 20
+    offset: Int! = 0
+    filters: NotificationFilters = null
+  ): NotificationConnection!
+  unreadNotificationCount: Int!
   getRuns(
     filterInput: RunFilterInput!
     runIds: [Int!] = null
@@ -647,6 +653,7 @@ input VideoFeedInputGQL @oneOf {
   followedByUserId: Int
   userId: Int
   allUsers: Boolean
+  home: Boolean
 }
 
 type MakePercentageIntervalGQL {
@@ -715,6 +722,37 @@ input MedalScope @oneOf {
   datetimeRange: DatetimeRangeAggregationInput
 }
 
+type NotificationConnection {
+  notifications: [NotificationGQL!]!
+  totalCount: Int!
+  unreadCount: Int!
+  hasMore: Boolean!
+}
+
+type NotificationGQL {
+  id: Int!
+  notificationType: NotificationTypeEnum!
+  actor: UserGQL!
+  videoId: Int
+  comment: CommentGQL
+  reactionType: String
+  isRead: Boolean!
+  createdAt: DateTime!
+  readAt: DateTime
+}
+
+enum NotificationTypeEnum {
+  COMMENT
+  COMMENT_REPLY
+  REACTION
+  FOLLOW
+}
+
+input NotificationFilters {
+  isRead: Boolean = null
+  notificationTypes: [NotificationTypeEnum!] = null
+}
+
 type GetRunsResult {
   runs: [RunGQL!]!
   count: Int
@@ -916,6 +954,10 @@ type Mutation {
     reason: ReportReasonEnum!
     customReason: String = null
   ): Boolean!
+  markNotificationAsRead(notificationId: Int!): Boolean!
+  markAllNotificationsAsRead: Boolean!
+  markNotificationsAsRead(notificationIds: [Int!]!): Boolean!
+  deleteNotification(notificationId: Int!): Boolean!
   addAnnotationToShot(
     shotId: Int!
     annotationName: String!