Make WP admins instructors too, and add an Access toggle page

A WordPress administrator previously inherited the studio-admin
capabilities but not `manage_availability`, so the studio owner running
as an admin had no way to reach "My Availability" or act as the
instructor — breaking single-instructor businesses.

Grant the instructor capabilities to administrators as well (via the
existing `user_has_cap` filter), and make both grants — studio-admin and
instructor — independently toggleable from a new Access admin page.

- RoleManager: extract `INSTRUCTOR_CAPS`; apply studio and instructor
  cap sets to administrators, each gated on a stored toggle (default on).
- AccessSettings + templates/admin/access.php: two options
  (`us_admin_grant_studio` / `us_admin_grant_instructor`), gated on the
  core `manage_options` capability so disabling a grant can never lock an
  administrator out of re-enabling it.
- AdminMenu: register the Access page after Studio Settings; keep the
  studio sidebar separator visible for any administrator.
- Tests for the toggles and the new settings reader; docs updated.

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

src/Auth/RoleManager.php

@@ -42,6 +42,26 @@ class RoleManager {
 		self::CAP_EXPORT_PAYMENTS,
 	];
 
+	/**
+	 * Capabilities granted to the `us_instructor` role, and implicitly to any
+	 * WordPress administrator (see {@see grantStudioCapsToAdministrators()}) so a
+	 * single-instructor studio owner can both run the business and teach from one
+	 * account — managing their own availability and lessons without being assigned
+	 * a separate `us_instructor` role.
+	 *
+	 * @var list<string>
+	 */
+	public const INSTRUCTOR_CAPS = [
+		self::CAP_MANAGE_AVAILABILITY,
+		self::CAP_MANAGE_OFFERINGS,
+		self::CAP_MANAGE_QUESTIONS,
+		self::CAP_VIEW_LESSONS,
+		self::CAP_VIEW_OWN_PAYMENTS,
+		self::CAP_EXPORT_PAYMENTS,
+	];
+
+	public function __construct( private AccessSettings $access = new AccessSettings() ) {}
+
 	public function register(): void {
 		add_action( 'init', [ $this, 'createRoles' ] );
 		add_filter( 'user_has_cap', [ $this, 'grantStudioCapsToAdministrators' ], 10, 1 );
@@ -62,18 +82,15 @@ class RoleManager {
 		}
 
 		if ( get_role( self::INSTRUCTOR ) === null ) {
+			$instructorCaps = [ 'read' => true ];
+			foreach ( self::INSTRUCTOR_CAPS as $cap ) {
+				$instructorCaps[ $cap ] = true;
+			}
+
 			add_role(
 				self::INSTRUCTOR,
 				__( 'Instructor', 'unsupervised-schedular' ),
-				[
-					'read'                        => true,
-					self::CAP_MANAGE_AVAILABILITY => true,
-					self::CAP_MANAGE_OFFERINGS    => true,
-					self::CAP_MANAGE_QUESTIONS    => true,
-					self::CAP_VIEW_LESSONS        => true,
-					self::CAP_VIEW_OWN_PAYMENTS   => true,
-					self::CAP_EXPORT_PAYMENTS     => true,
-				]
+				$instructorCaps
 			);
 		}
 
@@ -95,9 +112,14 @@ class RoleManager {
 	 *
 	 * The studio owner runs the site as an administrator (`manage_options`) and
 	 * should manage offerings, questions, policies, billing, and reports without
-	 * being assigned the separate `us_studio_admin` role. Applied dynamically via
-	 * the `user_has_cap` filter, so nothing is persisted and the grant disappears
-	 * when the plugin is deactivated.
+	 * being assigned the separate `us_studio_admin` role. The instructor
+	 * capabilities are granted too, so a single-instructor studio owner can manage
+	 * their own availability and lessons and act as the instructor from the same
+	 * account. Applied dynamically via the `user_has_cap` filter, so nothing is
+	 * persisted and the grant disappears when the plugin is deactivated.
+	 *
+	 * Both grants are independently toggleable from the Access settings page (see
+	 * {@see AccessSettings}); they default on, preserving the single-account setup.
 	 *
 	 * @param array<string, bool> $allcaps All capabilities currently held by the user.
 	 * @return array<string, bool>
@@ -107,8 +129,16 @@ class RoleManager {
 			return $allcaps;
 		}
 
-		foreach ( self::STUDIO_ADMIN_CAPS as $cap ) {
-			$allcaps[ $cap ] = true;
+		if ( $this->access->adminsAreStudioAdmins() ) {
+			foreach ( self::STUDIO_ADMIN_CAPS as $cap ) {
+				$allcaps[ $cap ] = true;
+			}
+		}
+
+		if ( $this->access->adminsAreInstructors() ) {
+			foreach ( self::INSTRUCTOR_CAPS as $cap ) {
+				$allcaps[ $cap ] = true;
+			}
 		}
 
 		return $allcaps;