feat(active-codes): Smart Activation Codes system

Pre-generated stock voucher codes that pair with an auto-created line and
count down only on the client's first activation. Full admin + reseller
management — list, generate wizard, batch manager, mass edit — plus an
activation portal and a public activation API.

- schema: activation_codes table (migration 019 + database.sql)
- domain: ActiveCodeService (generate / activate / mass actions / export /
  batch summary; view queries live here, not in the templates)
- admin + reseller controllers and views; PortalController + activation API
- nginx routes for /active_code.php and the active_code API endpoint
- wired into auth, users, reseller dispatcher, table/player APIs and navbar

Passes phpstan, phpcs, make gates, and the unit suite (524 tests).

src/Domain/User/UserRepository.php

@@ -393,6 +393,22 @@ class UserRepository {
 		return null;
 	}
 
+	/**
+	 * Fetch a line by username.
+	 *
+	 * @param string $rUsername Line username.
+	 * @return array|null The line row, or null if not found.
+	 */
+	public static function getLineByUsername($rUsername) {
+		$db = self::db();
+		$db->query('SELECT * FROM `lines` WHERE `username` = ?;', $rUsername);
+
+		if ($db->num_rows() == 1) {
+			return $db->get_row();
+		}
+		return null;
+	}
+
 	/**
 	 * Fetch a registered (panel) user by id.
 	 *
@@ -409,6 +425,16 @@ class UserRepository {
 		return null;
 	}
 
+	/**
+	 * Alias for getRegisteredUserById.
+	 *
+	 * @param int $rID User id.
+	 * @return array|null
+	 */
+	public static function getUserById($rID) {
+		return self::getRegisteredUserById($rID);
+	}
+
 	/**
 	 * List registered users under an owner.
 	 *