Upgrade PHPStan to 2.x and raise analysis level from 6 to 10

- Bump phpstan/phpstan ^2.0 and szepeviktor/phpstan-wordpress ^2.0
- Move the analysis level into phpstan.neon (single source) and raise it to 10
- Add Val, a runtime coercion helper that narrows untyped WordPress boundary
  values (wpdb rows, REST params, superglobals, options) with explicit checks
  instead of blind casts, plus unit tests
- Type value-object fromRow() params as stdClass (what wpdb returns) and map
  columns through Val so unexpected shapes degrade safely
- Use %i identifier placeholders for table names in all wpdb::prepare() calls
  so every query string is a literal and identifiers are escaped by WordPress;
  raises the minimum WordPress version to 6.2 where %i was introduced
- Guard wpdb::prepare() null result before wpdb::query() in updateTax()
- Fix nullable get_permalink()/strtotime() handling, list types at REST and
  capability call sites, dead null-coalescing on checked superglobals, and
  narrow get_users() results before mapping
- Register Val method names with the ValidatedSanitizedInput sniff so it
  validates the real sanitizer around each superglobal read
- Update repository unit tests for the %i placeholder arguments

Co-Authored-By: Claude Fable 5 <[email protected]>

src/GroupClass/EnrollmentEndpoint.php

@@ -10,6 +10,7 @@ use Unsupervised\Schedular\Payment\Payment;
 use Unsupervised\Schedular\Payment\PaymentService;
 use Unsupervised\Schedular\Policy\PolicyAcceptance;
 use Unsupervised\Schedular\Registration\RegistrationGate;
+use Unsupervised\Schedular\Val;
 
 class EnrollmentEndpoint {
 
@@ -20,6 +21,11 @@ class EnrollmentEndpoint {
 		private PaymentService $payments,
 	) {}
 
+	/**
+	 * Registers this endpoint's REST routes.
+	 *
+	 * @param non-falsy-string $route_namespace REST namespace the routes are registered under (e.g. `us-scheduler/v1`).
+	 */
 	public function registerRoutes( string $route_namespace ): void {
 		register_rest_route(
 			$route_namespace,
@@ -69,7 +75,7 @@ class EnrollmentEndpoint {
 	}
 
 	public function enroll( \WP_REST_Request $request ): \WP_REST_Response|\WP_Error {
-		$offeringId = absint( $request->get_param( 'offering_id' ) );
+		$offeringId = absint( Val::int( $request->get_param( 'offering_id' ) ) );
 		$offering   = $this->offerings->findById( $offeringId );
 
 		if ( null === $offering || Offering::KIND_GROUP_CLASS !== $offering->kind ) {
@@ -87,7 +93,7 @@ class EnrollmentEndpoint {
 		}
 
 		$answers            = $this->answers( $request );
-		$acceptedVersionIds = array_map( 'absint', (array) $request->get_param( 'accepted_policy_version_ids' ) );
+		$acceptedVersionIds = array_values( array_map( static fn( mixed $v ): int => absint( Val::int( $v ) ), (array) $request->get_param( 'accepted_policy_version_ids' ) ) );
 
 		$gateError = $this->gate->validate( $offeringId, $answers, $acceptedVersionIds );
 		if ( $gateError instanceof \WP_Error ) {
@@ -133,7 +139,7 @@ class EnrollmentEndpoint {
 	private function answers( \WP_REST_Request $request ): array {
 		$out = [];
 		foreach ( (array) $request->get_param( 'answers' ) as $questionId => $value ) {
-			$out[ (int) $questionId ] = sanitize_text_field( (string) $value );
+			$out[ (int) $questionId ] = sanitize_text_field( Val::string( $value ) );
 		}
 
 		return $out;
@@ -141,7 +147,7 @@ class EnrollmentEndpoint {
 
 	private function clientIp(): ?string {
 		// phpcs:ignore WordPress.Security.ValidatedSanitizedInput.InputNotSanitized, WordPress.Security.ValidatedSanitizedInput.MissingUnslash -- IP stored verbatim for audit.
-		$ip = sanitize_text_field( wp_unslash( $_SERVER['REMOTE_ADDR'] ?? '' ) );
+		$ip = sanitize_text_field( Val::string( wp_unslash( $_SERVER['REMOTE_ADDR'] ?? '' ) ) );
 
 		return '' !== $ip ? $ip : null;
 	}