Simplify Nested Routes with Shallow Resource Controllers

Use shallow nesting on resource routes to keep URLs concise while preserving parent-child relationships for creation and listing endpoints.

Deeply nested resource routes (such as `/posts/{post}/comments/{comment}/edit`) create unnecessarily long URLs and controller parameter signatures.

By chaining `->shallow()`, child resource routes that operate on a unique primary key automatically drop the parent URI segment:

use App\Http\Controllers\CommentController;
use Illuminate\Support\Facades\Route;

// Shallow resource routes
Route::resource('posts.comments', CommentController::class)->shallow();

/*
Generated URIs:
GET    /posts/{post}/comments           -> index (needs parent)
POST   /posts/{post}/comments           -> store (needs parent)
GET    /comments/{comment}              -> show (shallow)
GET    /comments/{comment}/edit         -> edit (shallow)
PUT    /comments/{comment}              -> update (shallow)
DELETE /comments/{comment}              -> destroy (shallow)
*/

• Eliminates redundant parent ID parameters in controller show, edit, update, and destroy actions
• Keeps nested resource URLs clean and user-friendly
• Retains parent routing context for index and store endpoints