Extend availability (durations, weekly recurrence, calendar); price offerings in dollars

Availability (#2):
- us_availability gains offering_id, duration_minutes (default 60), and
  recurrence_group; AvailabilitySlot carries the new fields.
- AvailabilityRepository::createWeeklySeries() generates N weekly rows
  sharing a recurrence_group; findAvailable() filters by offering and
  duration. Date math uses DateTimeImmutable::modify() (the no-debug CI
  regex `dd\(` matches `->add(`).
- REST GET filters by offering_id/duration_minutes; POST accepts
  duration_minutes, offering_id, recurrence (single|weekly) + weeks.
- Admin form adds duration, an offering picker, and one-off/weekly options
  (OfferingRepository wired into AvailabilityController).
- booking.js renders an agenda calendar (slots grouped by day, with
  duration). The richer booking UX lands with the booking-flow work.

Offering price in dollars:
- Switch us_offerings.price_cents (INT) to price DECIMAL(10,2); Offering
  uses float $price. Admin form and REST take dollars.
- Fix a pre-existing misalignment in the Offering insert/update $wpdb
  format arrays (billing_mode/capacity/is_active were mapped to the wrong
  specifiers, which would corrupt values) via a single COLUMN_FORMATS list.

Also bump PHPStan to --memory-limit=1G in the lint script; 128M now
crashes analysis as the codebase has grown.

Refs #2

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

src/Availability/AvailabilityEndpoint.php

@@ -19,15 +19,23 @@ class AvailabilityEndpoint {
 					'callback'            => [ $this, 'index' ],
 					'permission_callback' => [ $this, 'canBook' ],
 					'args'                => [
-						'instructor_id' => [
+						'instructor_id'    => [
 							'type'    => 'integer',
 							'default' => 0,
 						],
-						'from'          => [
+						'offering_id'      => [
+							'type'    => 'integer',
+							'default' => 0,
+						],
+						'duration_minutes' => [
+							'type'    => 'integer',
+							'default' => 0,
+						],
+						'from'             => [
 							'type'    => 'string',
 							'default' => '',
 						],
-						'to'            => [
+						'to'               => [
 							'type'    => 'string',
 							'default' => '',
 						],
@@ -38,16 +46,32 @@ class AvailabilityEndpoint {
 					'callback'            => [ $this, 'create' ],
 					'permission_callback' => [ $this, 'canManage' ],
 					'args'                => [
-						'start_dt' => [
+						'start_dt'         => [
 							'type'              => 'string',
 							'required'          => true,
 							'sanitize_callback' => 'sanitize_text_field',
 						],
-						'end_dt'   => [
+						'end_dt'           => [
 							'type'              => 'string',
 							'required'          => true,
 							'sanitize_callback' => 'sanitize_text_field',
 						],
+						'duration_minutes' => [
+							'type'    => 'integer',
+							'default' => 60,
+						],
+						'offering_id'      => [
+							'type'    => 'integer',
+							'default' => 0,
+						],
+						'recurrence'       => [
+							'type'    => 'string',
+							'default' => 'single',
+						],
+						'weeks'            => [
+							'type'    => 'integer',
+							'default' => 1,
+						],
 					],
 				],
 			]
@@ -69,6 +93,8 @@ class AvailabilityEndpoint {
 	public function index( \WP_REST_Request $request ): \WP_REST_Response {
 		$slots = $this->repository->findAvailable(
 			(int) $request->get_param( 'instructor_id' ),
+			(int) $request->get_param( 'offering_id' ),
+			(int) $request->get_param( 'duration_minutes' ),
 			(string) $request->get_param( 'from' ),
 			(string) $request->get_param( 'to' ),
 		);
@@ -77,12 +103,23 @@ class AvailabilityEndpoint {
 	}
 
 	public function create( \WP_REST_Request $request ): \WP_REST_Response {
+		$offeringId = absint( $request->get_param( 'offering_id' ) );
+		$duration   = absint( $request->get_param( 'duration_minutes' ) );
+
 		$slot = new AvailabilitySlot(
-			instructorId: get_current_user_id(),
-			startDt:      (string) $request->get_param( 'start_dt' ),
-			endDt:        (string) $request->get_param( 'end_dt' ),
+			instructorId:    get_current_user_id(),
+			startDt:         (string) $request->get_param( 'start_dt' ),
+			endDt:           (string) $request->get_param( 'end_dt' ),
+			durationMinutes: $duration > 0 ? $duration : 60,
+			offeringId:      $offeringId > 0 ? $offeringId : null,
 		);
 
+		if ( 'weekly' === $request->get_param( 'recurrence' ) ) {
+			$ids = $this->repository->createWeeklySeries( $slot, absint( $request->get_param( 'weeks' ) ) );
+
+			return new \WP_REST_Response( [ 'ids' => $ids ], 201 );
+		}
+
 		$id = $this->repository->insert( $slot );
 
 		return new \WP_REST_Response( [ 'id' => $id ], 201 );