refactor:공정 단계 completion_type 한글→영문 코드 전환

- completion_type 값을 한글(클릭 시 완료)에서 영문 코드(click_complete)로 변환
- FormRequest에 in 검증 규칙 추가 (click_complete, selection_complete, inspection_complete)
- 기존 데이터 마이그레이션 포함

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

app/Http/Requests/V1/ProcessStep/StoreProcessStepRequest.php

@@ -21,7 +21,7 @@ public function rules(): array
             'is_active' => ['nullable', 'boolean'],
             'connection_type' => ['nullable', 'string', 'max:20'],
             'connection_target' => ['nullable', 'string', 'max:255'],
-            'completion_type' => ['nullable', 'string', 'max:30'],
+            'completion_type' => ['nullable', 'string', 'in:click_complete,selection_complete,inspection_complete'],
         ];
     }
 

app/Http/Requests/V1/ProcessStep/UpdateProcessStepRequest.php

@@ -21,7 +21,7 @@ public function rules(): array
             'is_active' => ['nullable', 'boolean'],
             'connection_type' => ['nullable', 'string', 'max:20'],
             'connection_target' => ['nullable', 'string', 'max:255'],
-            'completion_type' => ['nullable', 'string', 'max:30'],
+            'completion_type' => ['nullable', 'string', 'in:click_complete,selection_complete,inspection_complete'],
         ];
     }