fix: PHP 8.3 TypeError in articles-list total count (int cast)

number_format() in PHP 8.3 strictly requires int|float; $wpdb->get_var()
returns string|null. Cast $total to (int) at point of assignment in
admin/partials/articles-list.php to fix HTTP 500 on Articles admin page.

Also add PHPUnit test covering the string->int cast contract.

Fixes #31. Version bump 2.5.0 -> 2.5.1.

Agent-Session: fix-articles-500-20260617

CHANGELOG.md

@@ -4,6 +4,11 @@ All notable changes to Peptide News Plugin are documented here.
 Format: [Keep a Changelog](https://keepachangelog.com/en/1.0.0/).
 Versioning: [Semantic Versioning](https://semver.org/).
 
+## [2.5.1] - 2026-06-17
+
+### Fixed
+- PHP 8.3 `TypeError` on Articles admin page: `number_format()` rejects the numeric string returned by `$wpdb->get_var()`. Cast `$total` to `(int)` at point of assignment in `admin/partials/articles-list.php` (#31).
+
 ## [2.5.0] — 2026-06-16
 
 ### Changed

admin/partials/articles-list.php

@@ -19,7 +19,7 @@ $per_page = 25;
 $offset  = ( $page - 1 ) * $per_page;
 
 // phpcs:ignore WordPress.DB.DirectDatabaseQuery.DirectQuery, WordPress.DB.DirectDatabaseQuery.NoCaching
-$total = $wpdb->get_var( "SELECT COUNT(*) FROM {$table}" );
+$total = (int) $wpdb->get_var( "SELECT COUNT(*) FROM {$table}" );
 // phpcs:ignore WordPress.DB.DirectDatabaseQuery.DirectQuery, WordPress.DB.DirectDatabaseQuery.NoCaching
 $articles = $wpdb->get_results( $wpdb->prepare(
 	"SELECT * FROM {$table} ORDER BY published_at DESC LIMIT %d OFFSET %d",

peptide-news-plugin.php

@@ -3,7 +3,7 @@
  * Plugin Name:       Peptide News Aggregator
  * Plugin URI:        https://github.com/peptiderepo/peptide-news-plugin
  * Description:       Aggregates and displays the latest peptide research news from multiple sources with click analytics and trend reporting.
- * Version:           2.5.0
+ * Version:           2.5.1
  * Author:            peptiderepo
  * Author URI:        https://github.com/peptiderepo
  * License:           GPL-2.0+
@@ -24,7 +24,7 @@ if ( ! defined( 'WPINC' ) ) {
 /**
  * Current plugin version — follows SemVer.
  */
-define( 'PEPTIDE_NEWS_VERSION', '2.5.0' );
+define( 'PEPTIDE_NEWS_VERSION', '2.5.1' );
 define( 'PEPTIDE_NEWS_PLUGIN_DIR', plugin_dir_path( __FILE__ ) );
 define( 'PEPTIDE_NEWS_PLUGIN_URL', plugin_dir_url( __FILE__ ) );
 define( 'PEPTIDE_NEWS_PLUGIN_BASENAME', plugin_basename( __FILE__ ) );

tests/unit/ArticlesListTotalCastTest.php

@@ -0,0 +1,32 @@
+<?php
+/**
+ * Test that articles list total count is cast to int.
+ *
+ * @package Peptide_News
+ */
+
+class ArticlesListTotalCastTest extends WP_UnitTestCase {
+    /**
+     * Verify that $wpdb->get_var returning a numeric string does not
+     * cause a TypeError in number_format() (PHP 8.3 strict typing).
+     */
+    public function test_total_cast_prevents_type_error() {
+        $total_as_string = '451'; // what $wpdb->get_var() returns
+        $total = (int) $total_as_string;
+        $this->assertIsInt( $total );
+        $this->assertSame( 451, $total );
+        // This should not throw TypeError on PHP 8.3
+        $formatted = number_format( $total );
+        $this->assertSame( '451', $formatted );
+    }
+
+    /**
+     * Verify null return (missing table) results in 0, not a TypeError.
+     */
+    public function test_null_total_cast_to_zero() {
+        $total = (int) null;
+        $this->assertSame( 0, $total );
+        $formatted = number_format( $total );
+        $this->assertSame( '0', $formatted );
+    }
+}