feat: add Devis and BesoinInformatique modules

- Devis: CRUD complet, génération PDF (dompdf), paramètres (DevisSetting)
- BesoinInformatique: CRUD complet avec gestion matériels/licences
- Migrations pour les 3 nouvelles tables
- Navigation mise à jour dans AuthenticatedLayout

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

database/migrations/2026_06_17_111413_create_devis_table.php

@@ -0,0 +1,39 @@
+<?php
+
+use Illuminate\Database\Migrations\Migration;
+use Illuminate\Database\Schema\Blueprint;
+use Illuminate\Support\Facades\Schema;
+
+return new class extends Migration
+{
+    /**
+     * Run the migrations.
+     */
+    public function up(): void
+    {
+        Schema::create('devis', function (Blueprint $table) {
+            $table->id();
+            $table->string('number')->unique();
+            $table->string('title');
+            $table->string('destinataire_type'); // 'commune', 'service_interne'
+            $table->string('destinataire_nom');
+            $table->string('referent')->nullable();
+            $table->date('date_devis');
+            $table->string('status')->default('draft'); // 'draft', 'sent', 'accepted', 'rejected'
+            $table->json('items')->nullable(); // details of items (type, designation, quantity, unit_price, total_price)
+            $table->decimal('total_ht', 15, 2)->default(0.00);
+            $table->decimal('tva_rate', 5, 2)->default(20.00);
+            $table->decimal('total_ttc', 15, 2)->default(0.00);
+            $table->text('notes')->nullable();
+            $table->timestamps();
+        });
+    }
+
+    /**
+     * Reverse the migrations.
+     */
+    public function down(): void
+    {
+        Schema::dropIfExists('devis');
+    }
+};