Add studio-defined account-registration questions

Studio admins can now define registration questions that every new student
answers as a required second step during signup, with each student's answers
shown under a "Registration Information" section in the admin.

Extends the existing Registration domain: us_questions gains a scope column
(offering | account) and a nullable offering_id, and account answers reuse
us_question_answers with registration_type = 'account'. Authoring reuses the
Offerings -> Questions page via an "Account signup" scope (studio-admin only).
The registration form becomes two steps (progressive enhancement via
assets/js/register.js; works without JS); required answers are validated before
the account is created and apply to all signup paths (invite, group link,
self-approval). StudentHistory::registrationInfo() powers the admin section.

Bumps the plugin version to 1.1.0 so dbDelta runs the schema migration.

Closes #90

Co-Authored-By: Claude Opus 4.8 <[email protected]>

src/Registration/QuestionController.php

@@ -23,8 +23,13 @@ class QuestionController {
 		$userId    = get_current_user_id();
 		$manageAll = current_user_can( RoleManager::CAP_MANAGE_INSTRUCTORS );
 
-		// phpcs:ignore WordPress.Security.NonceVerification.Recommended -- read-only offering selector.
-		$offeringId       = absint( Val::int( $_GET['offering_id'] ?? 0 ) );
+		// The selector posts either an offering id or the sentinel `account`.
+		// Account-signup questions are studio-wide, so only studio admins manage them.
+		// phpcs:ignore WordPress.Security.NonceVerification.Recommended -- read-only selector.
+		$selection    = sanitize_text_field( Val::string( wp_unslash( $_GET['offering_id'] ?? '' ) ) );
+		$accountScope = $manageAll && Question::SCOPE_ACCOUNT === $selection;
+
+		$offeringId       = $accountScope ? 0 : absint( Val::int( $selection ) );
 		$offeringList     = $manageAll ? $this->offerings->findAll() : $this->offerings->findAll( $userId );
 		$selectedOffering = $offeringId > 0 ? $this->offerings->findById( $offeringId ) : null;
 
@@ -33,7 +38,13 @@ class QuestionController {
 		}
 
 		$questions = null;
-		if ( null !== $selectedOffering ) {
+		if ( $accountScope ) {
+			if ( isset( $_POST['usc_action'] ) && check_admin_referer( 'usc_question_action' ) ) {
+				$this->handleFormAction( null );
+			}
+
+			$questions = $this->questions->findByScope( Question::SCOPE_ACCOUNT );
+		} elseif ( null !== $selectedOffering ) {
 			if ( isset( $_POST['usc_action'] ) && check_admin_referer( 'usc_question_action' ) ) {
 				$this->handleFormAction( $selectedOffering );
 			}
@@ -44,20 +55,24 @@ class QuestionController {
 		include USC_PLUGIN_DIR . 'templates/admin/questions.php';
 	}
 
-	private function handleFormAction( Offering $offering ): void {
+	/**
+	 * Handle an add/delete action for the given context: an offering, or account
+	 * scope when $offering is null.
+	 */
+	private function handleFormAction( ?Offering $offering ): void {
 		// Nonce is verified by the caller (renderPage) before this method runs.
 		// phpcs:disable WordPress.Security.NonceVerification.Missing
 		$action = sanitize_key( Val::string( wp_unslash( $_POST['usc_action'] ?? '' ) ) );
 
 		if ( 'add' === $action ) {
-			$this->addQuestion( (int) $offering->id );
+			$this->addQuestion( $offering );
 		}
 
 		if ( 'delete' === $action ) {
 			$questionId = absint( Val::int( $_POST['question_id'] ?? 0 ) );
 			if ( $questionId > 0 ) {
 				$question = $this->questions->findById( $questionId );
-				if ( $question && $question->offeringId === (int) $offering->id ) {
+				if ( $question && $this->belongsToContext( $question, $offering ) ) {
 					$this->questions->delete( $questionId );
 				}
 			}
@@ -65,7 +80,7 @@ class QuestionController {
 		// phpcs:enable WordPress.Security.NonceVerification.Missing
 	}
 
-	private function addQuestion( int $offeringId ): void {
+	private function addQuestion( ?Offering $offering ): void {
 		// phpcs:disable WordPress.Security.NonceVerification.Missing
 		$label     = sanitize_text_field( Val::string( wp_unslash( $_POST['label'] ?? '' ) ) );
 		$fieldType = sanitize_key( Val::string( wp_unslash( $_POST['field_type'] ?? Question::FIELD_TEXT ) ) );
@@ -76,17 +91,30 @@ class QuestionController {
 
 		$this->questions->insert(
 			new Question(
-				offeringId: $offeringId,
+				offeringId: null === $offering ? null : (int) $offering->id,
 				label:      $label,
 				fieldType:  $fieldType,
 				options:    $this->parseOptions( sanitize_textarea_field( Val::string( wp_unslash( $_POST['options'] ?? '' ) ) ) ),
 				isRequired: isset( $_POST['is_required'] ),
 				sortOrder:  absint( Val::int( $_POST['sort_order'] ?? 0 ) ),
+				scope:      null === $offering ? Question::SCOPE_ACCOUNT : Question::SCOPE_OFFERING,
 			)
 		);
 		// phpcs:enable WordPress.Security.NonceVerification.Missing
 	}
 
+	/**
+	 * Whether a question belongs to the current editing context — the given
+	 * offering, or account scope when $offering is null.
+	 */
+	private function belongsToContext( Question $question, ?Offering $offering ): bool {
+		if ( null === $offering ) {
+			return Question::SCOPE_ACCOUNT === $question->scope;
+		}
+
+		return $question->offeringId === (int) $offering->id;
+	}
+
 	private function canManageOffering( Offering $offering, int $userId, bool $manageAll ): bool {
 		return $manageAll || $offering->instructorId === $userId;
 	}