feat: L'Ami Fiduciaire V1.0.0 — full codebase with Story 0.1 complete

Initial commit of the L'Ami Fiduciaire SaaS platform built on Laravel 12,
Vue 3, Inertia.js 2, and Tailwind CSS 4.

Story 0.1 (rename folders to declarations in database) is implemented and
code-reviewed: migration, rollback, and 6 Pest tests all passing.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

app/Models/MediaDownload.php

@@ -0,0 +1,36 @@
+<?php
+
+namespace App\Models;
+
+use Illuminate\Database\Eloquent\Model;
+use Illuminate\Database\Eloquent\Relations\BelongsTo;
+
+class MediaDownload extends Model
+{
+    public const CREATED_AT = 'created_at';
+
+    public const UPDATED_AT = null;
+
+    protected $fillable = [
+        'media_id',
+        'user_id',
+        'downloaded_at',
+    ];
+
+    protected function casts(): array
+    {
+        return [
+            'downloaded_at' => 'datetime',
+        ];
+    }
+
+    public function media(): BelongsTo
+    {
+        return $this->belongsTo(\Spatie\MediaLibrary\MediaCollections\Models\Media::class);
+    }
+
+    public function user(): BelongsTo
+    {
+        return $this->belongsTo(User::class);
+    }
+}