chore:system user and events created by userid migrations (#5612)

## About the changes

Migrations for:
- Adds column is_system to users
- Inserts unleash_system_user id -1337 to users 

includes `is_system: false` in the activeUsers and activeAccounts where filter

Tested by running:
`
select * into users_pre_check from users where id > -1;
delete from users where id > -1;
`
before starting unleash, then inspecting users table after unleash has
started and verifying that an 'admin' user has been created.

---------

Co-authored-by: Christopher Kolstad <chriswk@getunleash.ai>

src/lib/db/account-store.ts

@@ -74,6 +74,7 @@ export class AccountStore implements IAccountStore {
     activeAccounts(): any {
         return this.db(TABLE).where({
             deleted_at: null,
+            is_system: false,
         });
     }
 

src/lib/db/user-store.ts

@@ -116,6 +116,7 @@ class UserStore implements IUserStore {
         return this.db(TABLE).where({
             deleted_at: null,
             is_service: false,
+            is_system: false,
         });
     }
 

src/migrations/20231222071533-unleash-system-user.js

@@ -0,0 +1,24 @@
+'use strict';
+
+exports.up = function (db, callback) {
+    db.runSql(
+        `
+        ALTER TABLE users ADD COLUMN IF NOT EXISTS is_system BOOLEAN NOT NULL DEFAULT FALSE;
+        INSERT INTO users
+          (id, name, username, email, created_by_user_id, is_system) 
+        VALUES
+          (-1337, 'Unleash System', 'unleash_system_user', 'system@getunleash.io', -1337, true);
+        `,
+        callback,
+    );
+};
+
+exports.down = function (db, callback) {
+    db.runSql(
+        `
+        ALTER TABLE users DROP COLUMN IF EXISTS is_system;
+        DELETE FROM users WHERE id = -1337;
+        `,
+        callback,
+    );
+};

src/test/e2e/system-user-migration.test.ts

@@ -0,0 +1,76 @@
+import { getDbConfig } from './helpers/database-config';
+import { createTestConfig } from '../config/test-config';
+import { getInstance } from 'db-migrate';
+import { log } from 'db-migrate-shared';
+import { Client } from 'pg';
+import { IDBOption } from 'lib/types';
+
+log.setLogLevel('error');
+
+async function initSchema(db: IDBOption): Promise<void> {
+    const client = new Client(db);
+    await client.connect();
+    await client.query(`DROP SCHEMA IF EXISTS ${db.schema} CASCADE`);
+    await client.query(`CREATE SCHEMA IF NOT EXISTS ${db.schema}`);
+    await client.end();
+}
+
+test('System user creation migration correctly sets is_system', async () => {
+    jest.setTimeout(15000);
+    const config = createTestConfig({
+        db: {
+            ...getDbConfig(),
+            pool: { min: 1, max: 4 },
+            schema: 'system_user_migration_test',
+            ssl: false,
+        },
+    });
+
+    await initSchema(config.db);
+
+    const e2e = {
+        ...config.db,
+        connectionTimeoutMillis: 2000,
+    };
+
+    // disable Intellij/WebStorm from setting verbose CLI argument to db-migrator
+    process.argv = process.argv.filter((it) => !it.includes('--verbose'));
+    const dbm = getInstance(true, {
+        cwd: `${__dirname}/../../`, // relative to src/test/e2e
+        config: { e2e },
+        env: 'e2e',
+    });
+
+    // Run all migrations up to, and including, this one, the last one before the system user migration
+    await dbm.up('20231221143955-feedback-table.js');
+
+    // Set up the test data
+    const client = new Client(config.db);
+    await client.connect();
+
+    await client.query(`
+        INSERT INTO "system_user_migration_test"."users"
+            (name, username, email, created_by_user_id) 
+        VALUES
+            ('Test Person', 'testperson', 'testperson@getunleash.io', 1);
+    `);
+
+    // Run the migration
+    await dbm.up('20231222071533-unleash-system-user.js');
+
+    // Check the results
+    const { rows: userResults } = await client.query(`
+        SELECT * FROM "system_user_migration_test"."users" ORDER BY id;
+    `);
+
+    await client.end();
+    await dbm.reset();
+
+    expect(userResults.length).toEqual(2);
+    expect(userResults[0].is_system).toEqual(true);
+    expect(userResults[0].id).toEqual(-1337);
+    expect(userResults[0].username).toEqual('unleash_system_user');
+    expect(userResults[1].is_system).toEqual(false);
+    expect(userResults[1].id).toEqual(1);
+    expect(userResults[1].username).toEqual('testperson');
+});