incr/app/Http/Controllers/Milestones/MilestoneController.php

<?php

declare(strict_types=1);

namespace App\Http\Controllers\Milestones;

use App\Http\Controllers\Controller;
use App\Models\User;
use Illuminate\Http\JsonResponse;
use Illuminate\Http\RedirectResponse;
use Illuminate\Http\Request;

class MilestoneController extends Controller
{
    public function store(Request $request): RedirectResponse
    {
        $validated = $request->validate([
            'target' => 'required|integer|min:1',
            'description' => 'required|string|max:255',
        ]);

        $tracker = User::default()->tracker;

        if (! $tracker) {
            return back()->withErrors(['tracker' => 'No tracker found. Please complete onboarding first.']);
        }

        $tracker->milestones()->create($validated);

        return back()->with('success', 'Milestone created successfully');
    }

    public function index(): JsonResponse
    {
        $tracker = User::default()->tracker;

        if (! $tracker) {
            return response()->json([]);
        }

        return response()->json($tracker->milestones()->orderBy('target')->get());
    }
}