feat:E-Sign 전자계약 서명 솔루션 MNG 프론트엔드 구현

- 컨트롤러 2개 (EsignController, EsignPublicController)
- 뷰 8개 (dashboard, create, detail, fields, send, sign/auth, sign/sign, sign/done)
- React 하이브리드 방식 (기존 Finance 패턴)
- 라우트 추가 (인증 esign/* + 공개 esign/sign/*)
- PDF.js 기반 서명 위치 설정
- signature_pad 기반 전자서명 입력
- OTP 본인인증 플로우

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

app/Http/Controllers/ESign/EsignController.php

@@ -0,0 +1,56 @@
+<?php
+
+namespace App\Http\Controllers\ESign;
+
+use App\Http\Controllers\Controller;
+use Illuminate\Http\Request;
+use Illuminate\View\View;
+use Symfony\Component\HttpFoundation\Response;
+
+class EsignController extends Controller
+{
+    public function dashboard(Request $request): View|Response
+    {
+        if ($request->header('HX-Request')) {
+            return response('', 200)->header('HX-Redirect', route('esign.dashboard'));
+        }
+
+        return view('esign.dashboard');
+    }
+
+    public function create(Request $request): View|Response
+    {
+        if ($request->header('HX-Request')) {
+            return response('', 200)->header('HX-Redirect', route('esign.create'));
+        }
+
+        return view('esign.create');
+    }
+
+    public function detail(Request $request, int $id): View|Response
+    {
+        if ($request->header('HX-Request')) {
+            return response('', 200)->header('HX-Redirect', route('esign.detail', $id));
+        }
+
+        return view('esign.detail', ['contractId' => $id]);
+    }
+
+    public function fields(Request $request, int $id): View|Response
+    {
+        if ($request->header('HX-Request')) {
+            return response('', 200)->header('HX-Redirect', route('esign.fields', $id));
+        }
+
+        return view('esign.fields', ['contractId' => $id]);
+    }
+
+    public function send(Request $request, int $id): View|Response
+    {
+        if ($request->header('HX-Request')) {
+            return response('', 200)->header('HX-Redirect', route('esign.send', $id));
+        }
+
+        return view('esign.send', ['contractId' => $id]);
+    }
+}

app/Http/Controllers/ESign/EsignPublicController.php

@@ -0,0 +1,25 @@
+<?php
+
+namespace App\Http\Controllers\ESign;
+
+use App\Http\Controllers\Controller;
+use Illuminate\Http\Request;
+use Illuminate\View\View;
+
+class EsignPublicController extends Controller
+{
+    public function auth(string $token): View
+    {
+        return view('esign.sign.auth', ['token' => $token]);
+    }
+
+    public function sign(string $token): View
+    {
+        return view('esign.sign.sign', ['token' => $token]);
+    }
+
+    public function done(string $token): View
+    {
+        return view('esign.sign.done', ['token' => $token]);
+    }
+}