feat: インスタンスのテーマカラーを設定できるように

packages/backend/migration/1644395759931-instance-theme-color.js

@@ -0,0 +1,13 @@
+const { MigrationInterface, QueryRunner } = require("typeorm");
+
+module.exports = class instanceThemeColor1644395759931 {
+    name = 'instanceThemeColor1644395759931'
+
+    async up(queryRunner) {
+        await queryRunner.query(`ALTER TABLE "meta" ADD "themeColor" character varying(512)`);
+    }
+
+    async down(queryRunner) {
+        await queryRunner.query(`ALTER TABLE "meta" DROP COLUMN "themeColor"`);
+    }
+}