Update relationships for book_categories table

app/Models/V1/Book.php

@@ -8,7 +8,7 @@
 use Illuminate\Database\Eloquent\Model;
 use Illuminate\Database\Eloquent\Relations\BelongsTo;
 use Illuminate\Database\Eloquent\Relations\HasMany;
-use Illuminate\Database\Eloquent\Relations\HasManyThrough;
+use Illuminate\Database\Eloquent\Relations\BelongsToMany;
 
 class Book extends Model
 {
@@ -66,10 +66,10 @@ public function reviews(): HasMany
     }
 
     /**
-     * Get all of the categories for the book.
+     * The categories that belong to the book.
      */
-    public function categories(): HasManyThrough
+    public function categories(): BelongsToMany
     {
-        return $this->hasManyThrough(Category::class, BookCategory::class);
+        return $this->belongsToMany(Category::class, "book_categories");
     }
 }

app/Models/V1/Category.php

@@ -4,7 +4,7 @@
 
 use Illuminate\Database\Eloquent\Factories\HasFactory;
 use Illuminate\Database\Eloquent\Model;
-use Illuminate\Database\Eloquent\Relations\HasManyThrough;
+use Illuminate\Database\Eloquent\Relations\BelongsToMany;
 
 class Category extends Model
 {
@@ -20,10 +20,10 @@ class Category extends Model
     ];
 
     /**
-     * Get all of the books for the category.
+     * The books that belong to the category.
      */
-    public function books(): HasManyThrough
+    public function books(): BelongsToMany
     {
-        return $this->hasManyThrough(Book::class, BookCategory::class);
+        return $this->belongsToMany(Book::class, "book_categories");
     }
 }