feat: Pipeline Settings M2 — decompose Content/AI Models/Sources into per-step panels + Global Content Context (#172, v0.24.0)

Relocates Content/AI Models/Sources fields into the per-step Pipeline panels; adds a Global Content Context block; retires the 3 duplicate Settings tabs. Option keys unchanged (no migration). QA APPROVE for 80d8e5f; CI green.

Agent-Session: pipeline-settings-m2-merge

includes/admin/class-pipeline-settings-option-fields.php

@@ -0,0 +1,125 @@
+<?php
+declare(strict_types=1);
+
+/**
+ * phpcs:ignore WordPress.Files.FileName.InvalidClassFileName -- class naming convention differs from WordPress standard
+ *
+ * Per-step-context option field definitions for the Pipeline Settings page.
+ *
+ * What: Central registry mapping step context identifiers to their editable
+ *       wp_option fields. Provides allowlist enforcement, field-type metadata,
+ *       and a single sanitize_option() entry point used by the save handler.
+ *       Fields were previously under Settings tabs (AI Models, Content, Sources)
+ *       retired in M2 — the wp_options themselves are unchanged, only the UI
+ *       surface that edits them has moved.
+ * Who calls it: PRAutoBlogger_Pipeline_Settings_Save_Handler (save_step_settings),
+ *               PRAutoBlogger_Pipeline_Settings_Renderer (view data assembly).
+ * Dependencies: PRAutoBlogger_Pipeline_Settings_Option_Fields_Data (field arrays).
+ *
+ * @see admin/class-pipeline-settings-option-fields-data.php — Raw field arrays per context.
+ * @see admin/class-pipeline-settings-save-handler.php       — save_step_settings dispatch.
+ * @see admin/class-pipeline-settings-renderer.php           — passes field values to template.
+ * @see CONVENTIONS.md §Retired Settings Tabs                — retirement pattern.
+ */
+class PRAutoBlogger_Pipeline_Settings_Option_Fields {
+
+	/**
+	 * All step context identifiers.
+	 *
+	 * @return string[]
+	 */
+	public static function contexts(): array {
+		return array( 'global', 'research', 'analysis', 'writer', 'editorial' );
+	}
+
+	/**
+	 * All allowed option names across every context (for allowlist enforcement).
+	 *
+	 * @return string[]
+	 */
+	public static function allowed_options(): array {
+		$names = array();
+		foreach ( self::contexts() as $ctx ) {
+			foreach ( self::get_fields_for_context( $ctx ) as $field ) {
+				$names[] = $field['id'];
+			}
+		}
+		return array_unique( $names );
+	}
+
+	/**
+	 * Field definitions for a given step context.
+	 *
+	 * Each field definition array contains at minimum:
+	 *   id      string  wp_option name.
+	 *   type    string  'textarea'|'select'|'number'|'toggle'|'checkboxes'.
+	 * Additional keys per type:
+	 *   options array   For 'select': key => label map of allowed values.
+	 *   choices array   For 'checkboxes': key => label map.
+	 *   min/max int     For 'number': enforced bounds.
+	 *   default mixed   Fallback when option is not set.
+	 *   label   string  Human-readable field label.
+	 *   description string  Help text shown below the field.
+	 *
+	 * @param string $context One of self::contexts().
+	 * @return array<int, array<string, mixed>>
+	 */
+	public static function get_fields_for_context( string $context ): array {
+		return PRAutoBlogger_Pipeline_Settings_Option_Fields_Data::fields_for( $context );
+	}
+
+	/**
+	 * Sanitize a raw POST value for a single field.
+	 *
+	 * Handles each field type independently: textarea → sanitize_textarea_field,
+	 * select → key validated against the options allowlist, number → absint +
+	 * bounds clamp, toggle → '0'|'1', checkboxes → JSON array of allowed keys.
+	 *
+	 * @param mixed                $value Raw value from $_POST.
+	 * @param array<string, mixed> $field Field definition from get_fields_for_context().
+	 * @return mixed Sanitized value ready for update_option().
+	 */
+	public static function sanitize_option( mixed $value, array $field ): mixed {
+		$type = (string) ( $field['type'] ?? 'textarea' );
+
+		switch ( $type ) {
+			case 'textarea':
+				return sanitize_textarea_field( (string) $value );
+
+			case 'toggle':
+				return ( '1' === (string) $value ) ? '1' : '0';
+
+			case 'number':
+				$int = absint( $value );
+				if ( isset( $field['min'] ) && $int < (int) $field['min'] ) {
+					$int = (int) $field['min'];
+				}
+				if ( isset( $field['max'] ) && $int > (int) $field['max'] ) {
+					$int = (int) $field['max'];
+				}
+				return $int;
+
+			case 'select':
+				$key     = sanitize_key( (string) $value );
+				$allowed = array_keys( (array) ( $field['options'] ?? array() ) );
+				return in_array( $key, $allowed, true ) ? $key : (string) ( $field['default'] ?? '' );
+
+			case 'checkboxes':
+				if ( ! is_array( $value ) ) {
+					$value = array();
+				}
+				$allowed  = array_keys( (array) ( $field['choices'] ?? array() ) );
+				$filtered = array();
+				foreach ( $value as $item ) {
+					$item = sanitize_key( (string) $item );
+					if ( in_array( $item, $allowed, true ) ) {
+						$filtered[] = $item;
+					}
+				}
+				return wp_json_encode( $filtered );
+
+			default:
+				return sanitize_text_field( (string) $value );
+		}
+	}
+}