feat: persistent memories (#8330)

* feat: persistent memories

* refactor: use new add/remove asset utility

server/src/entities/memory.entity.ts

@@ -0,0 +1,67 @@
+import { AssetEntity } from 'src/entities/asset.entity';
+import { UserEntity } from 'src/entities/user.entity';
+import {
+  Column,
+  CreateDateColumn,
+  DeleteDateColumn,
+  Entity,
+  JoinTable,
+  ManyToMany,
+  ManyToOne,
+  PrimaryGeneratedColumn,
+  UpdateDateColumn,
+} from 'typeorm';
+
+export enum MemoryType {
+  /** pictures taken on this day X years ago */
+  ON_THIS_DAY = 'on_this_day',
+}
+
+export type OnThisDayData = { year: number };
+
+export interface MemoryData {
+  [MemoryType.ON_THIS_DAY]: OnThisDayData;
+}
+
+@Entity('memories')
+export class MemoryEntity<T extends MemoryType = MemoryType> {
+  @PrimaryGeneratedColumn('uuid')
+  id!: string;
+
+  @CreateDateColumn({ type: 'timestamptz' })
+  createdAt!: Date;
+
+  @UpdateDateColumn({ type: 'timestamptz' })
+  updatedAt!: Date;
+
+  @DeleteDateColumn({ type: 'timestamptz' })
+  deletedAt?: Date;
+
+  @ManyToOne(() => UserEntity, { onDelete: 'CASCADE', onUpdate: 'CASCADE', nullable: false })
+  owner!: UserEntity;
+
+  @Column()
+  ownerId!: string;
+
+  @Column()
+  type!: T;
+
+  @Column({ type: 'jsonb' })
+  data!: MemoryData[T];
+
+  /** unless set to true, will be automatically deleted in the future */
+  @Column({ default: false })
+  isSaved!: boolean;
+
+  /** memories are sorted in ascending order by this value */
+  @Column({ type: 'timestamptz' })
+  memoryAt!: Date;
+
+  /** when the user last viewed the memory */
+  @Column({ type: 'timestamptz', nullable: true })
+  seenAt?: Date;
+
+  @ManyToMany(() => AssetEntity)
+  @JoinTable()
+  assets!: AssetEntity[];
+}