feat:ai_configs 테이블 마이그레이션 추가

- AI API 설정 테이블 (Gemini, Claude, OpenAI 지원)
- provider별 활성화 상태 관리
- 명함 OCR 시스템을 위한 기반 구조

database/migrations/2026_01_27_100000_create_ai_configs_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('ai_configs', function (Blueprint $table) {
+            $table->id();
+            $table->string('name', 50)->comment('설정 이름 (Gemini, Claude 등)');
+            $table->string('provider', 30)->comment('제공자 (gemini, claude, openai)');
+            $table->string('api_key', 255)->comment('API 키');
+            $table->string('model', 100)->comment('모델명 (gemini-2.0-flash 등)');
+            $table->string('base_url', 255)->nullable()->comment('API Base URL');
+            $table->text('description')->nullable()->comment('설명');
+            $table->boolean('is_active')->default(false)->comment('활성화 여부 (provider당 1개만 활성화)');
+            $table->json('options')->nullable()->comment('추가 옵션 (JSON)');
+            $table->timestamps();
+            $table->softDeletes();
+
+            $table->index('provider');
+            $table->index(['provider', 'is_active']);
+        });
+    }
+
+    /**
+     * Reverse the migrations.
+     */
+    public function down(): void
+    {
+        Schema::dropIfExists('ai_configs');
+    }
+};