docs: add PHPDoc documentation for all hooks

Add comprehensive PHPDoc documentation for all 24 filters and 2 actions
in the Ad Code Manager plugin, improving discoverability and developer
experience.

Documented filters include:
- Configuration: acm_register_provider_slug, acm_provider_slug,
  acm_whitelisted_script_urls, acm_whitelisted_conditionals,
  acm_logical_operator, acm_manage_ads_cap, acm_ad_tag_ids,
  acm_ad_code_args
- Rendering: acm_output_html, acm_output_tokens,
  acm_output_html_after_tokens_processed, acm_disable_ad_rendering,
  acm_wrapper_classes (already documented in #188)
- Matching: acm_display_ad_codes_without_conditionals,
  acm_conditional_args, acm_reset_postdata_before_match,
  acm_matching_ad_code_cache_expiration
- Admin: acm_list_table_columns, acm_list_table_per_page,
  acm_validate_ad_code, acm_allowed_get_posts_args, acm_ad_code_count
- Other: acm_default_url, acm_should_do_robotstxt,
  acm_robotstxt_disallow

Documented actions:
- acm_tag: Displays an ad tag on the frontend
- acm_options_form: Fires in the options form

Fixes #157

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

Author: GaryJones

src/class-acm-provider.php

@@ -33,7 +33,15 @@ public function __construct() {
 			);
 		}
 		/**
-		 * Configuration filter: acm_ad_code_args
+		 * Filters the ad code arguments/fields for a provider.
+		 *
+		 * This filter is also applied in the main Ad_Code_Manager class after
+		 * provider instantiation. It allows modification of the fields displayed
+		 * in the admin UI for this provider's ad codes.
+		 *
+		 * @since 0.1
+		 *
+		 * @param array $ad_code_args Array of field configurations.
 		 */
 		$this->ad_code_args = apply_filters( 'acm_ad_code_args', $this->ad_code_args );
 
@@ -44,6 +52,17 @@ public function __construct() {
 		}
 
 		if ( ! empty( $this->crawler_user_agent ) ) {
+			/**
+			 * Filters whether to add robots.txt rules for ad crawlers.
+			 *
+			 * When a provider has a crawler_user_agent defined, this filter
+			 * controls whether rules are added to robots.txt for that crawler.
+			 *
+			 * @since 0.1
+			 *
+			 * @param bool         $should_do Whether to add robots.txt rules. Default true.
+			 * @param ACM_Provider $provider  The provider instance.
+			 */
 			$should_do_robotstxt = apply_filters( 'acm_should_do_robotstxt', true, $this );
 
 			if ( true === $should_do_robotstxt ) {
@@ -63,6 +82,18 @@ public function action_do_robotstxt() {
 			$disallowed[] = '';
 		}
 
+		/**
+		 * Filters the disallowed paths for ad crawlers in robots.txt.
+		 *
+		 * Allows modification of which paths should be disallowed for the
+		 * ad network's crawler in the robots.txt file.
+		 *
+		 * @since 0.1
+		 *
+		 * @param array        $disallowed Array of paths to disallow. Default array('')
+		 *                                 or array('/') if blog is not public.
+		 * @param ACM_Provider $provider   The provider instance.
+		 */
 		$disallowed = apply_filters( 'acm_robotstxt_disallow', $disallowed, $this );
 
 		// If we have no disallows to add, don't add anything (including User-agent).

src/class-acm-wp-list-table.php

@@ -25,6 +25,17 @@ function __construct( $params = array() ) {
 	 * @return array $columns, the array of columns to use with the table
 	 */
 	function get_columns() {
+		/**
+		 * Filters the columns displayed in the ad codes list table.
+		 *
+		 * Allows providers to customise which columns appear in the admin list table.
+		 * Note: 'cb', 'id', 'priority', 'operator', and 'conditionals' are required
+		 * and will be added automatically if missing.
+		 *
+		 * @since 0.1.3
+		 *
+		 * @param array $columns Associative array of column IDs and labels.
+		 */
 		$columns = apply_filters(
 			'acm_list_table_columns',
 			array(
@@ -34,7 +45,7 @@ function get_columns() {
 				'priority'     => __( 'Priority', 'ad-code-manager' ),
 				'operator'     => __( 'Logical Operator', 'ad-code-manager' ),
 				'conditionals' => __( 'Conditionals', 'ad-code-manager' ),
-			) 
+			)
 		);
 		// Fail-safe for misconfiguration
 		$required_before = array(
@@ -83,7 +94,13 @@ function prepare_items() {
 		// Number of elements in your table?
 		$totalitems = count( $this->items ); // return the total number of affected rows
 
-		// How many to display per page?
+		/**
+		 * Filters the number of ad codes displayed per page in the list table.
+		 *
+		 * @since 0.1.3
+		 *
+		 * @param int $per_page Number of ad codes per page. Default 25.
+		 */
 		$perpage = apply_filters( 'acm_list_table_per_page', 25 );
 
 		// Which page is this?