feat: product team members

Co-Authored-By: Claude Sonnet 5.5 <noreply@anthropic.com>

app/Models/Product.php

@@ -138,6 +138,17 @@ class Product extends Model
         return $this->hasMany(PricingPlan::class)->orderBy('position')->orderBy('id');
     }
 
+    /**
+     * Get the team members of the product (besides the submitter).
+     */
+    public function members(): BelongsToMany
+    {
+        return $this->belongsToMany(User::class, 'product_members')
+            ->withPivot('role')
+            ->withTimestamps()
+            ->orderBy('product_members.id');
+    }
+
     /**
      * Get the user that owns the product.
      */