chore(angular-react): Migrate FavoriteButtonComponent to React

src/app/features/article/components/FavoriteButton.tsx

@@ -0,0 +1,105 @@
+import React, { useState, useCallback } from 'react';
+
+interface Article {
+  slug: string;
+  title: string;
+  description: string;
+  body: string;
+  tagList: string[];
+  createdAt: string;
+  updatedAt: string;
+  favorited: boolean;
+  favoritesCount: number;
+  author: {
+    username: string;
+    bio: string;
+    image: string;
+    following: boolean;
+  };
+}
+
+interface FavoriteButtonProps {
+  article: Article;
+  children?: React.ReactNode;
+  /** Called after a successful toggle. Receives the new `favorited` state. */
+  onToggle?: (favorited: boolean) => void;
+  /** Whether the current user is authenticated. */
+  isAuthenticated?: boolean;
+  /** Callback to navigate when user is not authenticated. */
+  onNavigateToRegister?: () => void;
+  /**
+   * Service function to favorite an article by slug.
+   * TODO: Wire up to actual ArticlesService when integrating.
+   */
+  onFavorite?: (slug: string) => Promise<void>;
+  /**
+   * Service function to unfavorite an article by slug.
+   * TODO: Wire up to actual ArticlesService when integrating.
+   */
+  onUnfavorite?: (slug: string) => Promise<void>;
+}
+
+/**
+ * React equivalent of the Angular `FavoriteButtonComponent`.
+ *
+ * Renders a favorite/unfavorite button for an article.
+ * Uses `<ng-content>` equivalent via `props.children`.
+ * Mirrors the Angular signal-based `isSubmitting` state with `useState`.
+ */
+export const FavoriteButton: React.FC<FavoriteButtonProps> = ({
+  article,
+  children,
+  onToggle,
+  isAuthenticated = false,
+  onNavigateToRegister,
+  onFavorite,
+  onUnfavorite,
+}) => {
+  const [isSubmitting, setIsSubmitting] = useState(false);
+
+  const toggleFavorite = useCallback(async () => {
+    setIsSubmitting(true);
+
+    if (!isAuthenticated) {
+      onNavigateToRegister?.();
+      setIsSubmitting(false);
+      return;
+    }
+
+    try {
+      if (!article.favorited) {
+        if (onFavorite) {
+          await onFavorite(article.slug);
+        } else {
+          return;
+        }
+      } else {
+        if (onUnfavorite) {
+          await onUnfavorite(article.slug);
+        } else {
+          return;
+        }
+      }
+      onToggle?.(!article.favorited);
+    } catch {
+      // Error handling — matches Angular's error callback (no-op)
+    } finally {
+      setIsSubmitting(false);
+    }
+  }, [article, isAuthenticated, onFavorite, onUnfavorite, onToggle, onNavigateToRegister]);
+
+  const buttonClass = [
+    'btn',
+    'btn-sm',
+    isSubmitting ? 'disabled' : '',
+    article.favorited ? 'btn-primary' : 'btn-outline-primary',
+  ]
+    .filter(Boolean)
+    .join(' ');
+
+  return (
+    <button className={buttonClass} onClick={toggleFavorite} disabled={isSubmitting}>
+      <i className="ion-heart"></i> {children}
+    </button>
+  );
+};