refactor: prefix Mi for all entities (#11719)

* wip

* wip

* wip

* wip

* Update RepositoryModule.ts

* wip

* wip

* wip

* Revert "wip"

This reverts commit c1c13b37d2.

packages/backend/src/models/entities/UsedUsername.ts

@@ -5,8 +5,8 @@
 
 import { PrimaryColumn, Entity, Column } from 'typeorm';
 
-@Entity()
-export class UsedUsername {
+@Entity('used_username')
+export class MiUsedUsername {
 	@PrimaryColumn('varchar', {
 		length: 128,
 	})
@@ -15,7 +15,7 @@ export class UsedUsername {
 	@Column('timestamp with time zone')
 	public createdAt: Date;
 
-	constructor(data: Partial<UsedUsername>) {
+	constructor(data: Partial<MiUsedUsername>) {
 		if (data == null) return;
 
 		for (const [k, v] of Object.entries(data)) {