refactor(deposits): remove refund approval remnants

apps/server/src/database/database-migrations.service.ts

@@ -15,6 +15,7 @@ export class DatabaseMigrationsService implements OnApplicationBootstrap {
     await this.normalizeClassDates();
     await this.protectAttendanceHistory();
     await this.removeUnusedClassroomColumns();
+    await this.cleanupDepositRefundColumns();
   }
 
   private async removeUnusedClassroomColumns(): Promise<void> {
@@ -36,6 +37,44 @@ export class DatabaseMigrationsService implements OnApplicationBootstrap {
     }
   }
 
+  private async cleanupDepositRefundColumns(): Promise<void> {
+    const runner = this.dataSource.createQueryRunner();
+    await runner.connect();
+    try {
+      const tables = await runner.getTables(['deposits']);
+      if (tables.length === 0) return;
+
+      const table = await runner.getTable('deposits');
+      const columnNames = new Set(table?.columns.map((column) => column.name) ?? []);
+      for (const [legacyName, currentName] of [
+        ['refund_approved_by', 'refunded_by'],
+        ['refund_approved_at', 'refunded_at'],
+      ] as const) {
+        if (!columnNames.has(legacyName)) continue;
+
+        if (columnNames.has(currentName)) {
+          await runner.query(
+            `UPDATE deposits SET ${currentName} = COALESCE(${currentName}, ${legacyName})`,
+          );
+          await runner.dropColumn('deposits', legacyName);
+        } else {
+          await runner.renameColumn('deposits', legacyName, currentName);
+          columnNames.add(currentName);
+        }
+        columnNames.delete(legacyName);
+      }
+
+      for (const columnName of ['refund_status', 'refund_requested_at', 'refund_rejected_reason']) {
+        if (columnNames.has(columnName)) {
+          await runner.dropColumn('deposits', columnName);
+          columnNames.delete(columnName);
+        }
+      }
+    } finally {
+      await runner.release();
+    }
+  }
+
   private async ensureAiConfigTable(): Promise<void> {
     const runner = this.dataSource.createQueryRunner();
     await runner.connect();