feat(api-explorer): Phase 1 기본 구조 및 OpenAPI 파싱 구현

- Config: api-explorer.php (환경, 보안, 캐시 설정)
- Migration: api_bookmarks, api_templates, api_histories, api_environments
- Model: ApiBookmark, ApiTemplate, ApiHistory, ApiEnvironment
- Service: OpenApiParserService, ApiRequestService, ApiExplorerService
- Controller: ApiExplorerController (CRUD, 실행, 히스토리)
- View: 3-Panel 레이아웃 (sidebar, request, response, history)
- Route: 23개 엔드포인트 등록

Swagger UI 대체 개발 도구, HTMX 기반 SPA 경험

app/Models/DevTools/ApiBookmark.php

@@ -0,0 +1,67 @@
+<?php
+
+namespace App\Models\DevTools;
+
+use App\Models\User;
+use Illuminate\Database\Eloquent\Model;
+use Illuminate\Database\Eloquent\Relations\BelongsTo;
+
+/**
+ * API 즐겨찾기 모델
+ *
+ * @property int $id
+ * @property int $user_id
+ * @property string $endpoint
+ * @property string $method
+ * @property string|null $display_name
+ * @property int $display_order
+ * @property string|null $color
+ * @property \Illuminate\Support\Carbon|null $created_at
+ * @property \Illuminate\Support\Carbon|null $updated_at
+ */
+class ApiBookmark extends Model
+{
+    protected $fillable = [
+        'user_id',
+        'endpoint',
+        'method',
+        'display_name',
+        'display_order',
+        'color',
+    ];
+
+    protected $casts = [
+        'display_order' => 'integer',
+    ];
+
+    /**
+     * 사용자 관계
+     */
+    public function user(): BelongsTo
+    {
+        return $this->belongsTo(User::class);
+    }
+
+    /**
+     * 기본 정렬 스코프
+     */
+    public function scopeOrdered($query)
+    {
+        return $query->orderBy('display_order')->orderBy('created_at');
+    }
+
+    /**
+     * HTTP 메서드 배지 색상
+     */
+    public function getMethodColorAttribute(): string
+    {
+        return match (strtoupper($this->method)) {
+            'GET' => 'green',
+            'POST' => 'blue',
+            'PUT' => 'yellow',
+            'PATCH' => 'orange',
+            'DELETE' => 'red',
+            default => 'gray',
+        };
+    }
+}