fix:명함등록(영업권) 목록에서 계약 버튼 제거

- 명함 등록 = 영업시작의 개념으로, 별도 계약 버튼 불필요
- 상세, 수정, 삭제 버튼만 유지

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

resources/views/sales/prospects/index.blade.php

@@ -117,13 +117,6 @@ class="w-full px-4 py-2 border border-gray-300 rounded-lg focus:outline-none foc
                             <button type="button" onclick="openProspectShowModal({{ $prospect->id }})" class="text-blue-600 hover:text-blue-900 mr-3">상세</button>
                             @if(!$prospect->isConverted())
                             <button type="button" onclick="openProspectEditModal({{ $prospect->id }})" class="text-indigo-600 hover:text-indigo-900 mr-3">수정</button>
-                            @if($prospect->isActive())
-                            <form action="{{ route('sales.prospects.convert', $prospect->id) }}" method="POST" class="inline"
-                                  onsubmit="return confirm('계약 처리하시겠습니까?')">
-                                @csrf
-                                <button type="submit" class="text-green-600 hover:text-green-900 mr-3">계약</button>
-                            </form>
-                            @endif
                             <form action="{{ route('sales.prospects.destroy', $prospect->id) }}" method="POST" class="inline"
                                   onsubmit="return confirm('정말 삭제하시겠습니까?')">
                                 @csrf