feat(cupang): 출고방식 파렛트, 상태/문서번호 폼 제거, 폼·상세 레이아웃 개편

- 출고방식 선택지에 "파렛트" 추가
- 신규/수정 폼에서 상태·문서번호 입력 제거 (status는 작성중 기본 + 취소처리로만 변경)
- document_no DB 컬럼 제거: init.sql 반영 + 기존 DB용 002 드롭 마이그레이션(승인 후 실행)
- 폼: 공통 헤더(좌) / 품목 라인(우) 2열 배치
- 상세: 엑셀·상태변경 버튼 삭제, ◀◀ 달력(검정) 좌측, 수정 우측 정렬, 문서번호 표시 제거

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

app/modules/cupang/templates/cupang/detail.html

@@ -6,18 +6,7 @@
 <section class="cpg">
 
   <div class="erp-page-actions cpg-actions">
-    <a class="erp-btn erp-btn-primary" href="/cupang/{{ shipment.id }}/edit">수정</a>
-    <a class="erp-btn erp-btn-outline" href="/cupang/{{ shipment.id }}/export">엑셀</a>
-    <a class="erp-btn erp-btn-outline" href="/cupang/?date={{ shipment.ship_date }}">달력으로</a>
-
-    <form method="post" action="/cupang/{{ shipment.id }}/status" class="cpg-inline-form">
-      <select class="erp-select" name="status">
-        {% for s in statuses %}
-        <option value="{{ s }}" {% if shipment.status == s %}selected{% endif %}>{{ s }}</option>
-        {% endfor %}
-      </select>
-      <button type="submit" class="erp-btn erp-btn-outline">상태 변경</button>
-    </form>
+    <a class="erp-btn erp-btn-primary" href="/cupang/?date={{ shipment.ship_date }}">◀◀ 달력</a>
 
     <form method="post" action="/cupang/{{ shipment.id }}/delete" class="cpg-inline-form"
           onsubmit="return confirm('이 출고 묶음을 취소 처리합니다(상태=취소). 계속할까요?');">
@@ -28,6 +17,8 @@
           onsubmit="return confirm('이 출고를 완전 삭제합니다(복구 불가, 품목 포함). 계속할까요?');">
       <button type="submit" class="erp-btn erp-btn-danger">삭제</button>
     </form>
+
+    <a class="erp-btn erp-btn-primary cpg-push-right" href="/cupang/{{ shipment.id }}/edit">수정</a>
   </div>
 
   <!-- 헤더 -->
@@ -48,7 +39,6 @@
       <div><dt>입고센터</dt><dd>{{ shipment.center_name_snapshot or '—' }}</dd></div>
       <div><dt>출고방식</dt><dd>{{ shipment.ship_method }}</dd></div>
       <div><dt>작업자</dt><dd>{{ shipment.worker or '—' }}</dd></div>
-      <div><dt>문서번호</dt><dd>{{ shipment.document_no or '—' }}</dd></div>
       <div class="cpg-full"><dt>출고/박스 요약</dt><dd>{{ shipment.outbound_summary or '—' }}</dd></div>
       <div class="cpg-full"><dt>메모</dt><dd>{{ shipment.memo or '—' }}</dd></div>
     </dl>

app/modules/cupang/templates/cupang/form.html

@@ -9,8 +9,10 @@
   <form id="cpg-form" method="post" action="{{ action }}">
     <input type="hidden" name="lines_json" id="cpg-lines-json" value="[]" />
 
-    <!-- ── 공통 헤더 ── -->
-    <div class="erp-card cpg-form-card">
+    <div class="cpg-form-2col">
+
+    <!-- ── 공통 헤더 (왼쪽) ── -->
+    <div class="erp-card cpg-form-card cpg-form-head">
       <div class="cpg-card-head"><h2>공통 헤더</h2></div>
       <div class="cpg-header-grid">
         <label class="erp-field"><span>작성일 *</span>
@@ -45,17 +47,6 @@
         <label class="erp-field"><span>작업자</span>
           <input class="erp-input" type="text" name="worker"
                  value="{{ shipment.worker if shipment else '' }}" /></label>
-
-        {% if mode == 'new' %}
-        <label class="erp-field"><span>상태</span>
-          <select class="erp-select" name="status">
-            {% for s in statuses %}<option value="{{ s }}">{{ s }}</option>{% endfor %}
-          </select></label>
-        {% endif %}
-
-        <label class="erp-field"><span>문서번호(선택)</span>
-          <input class="erp-input" type="text" name="document_no"
-                 value="{{ shipment.document_no or '' if shipment else '' }}" /></label>
       </div>
 
       <label class="erp-field cpg-full"><span>출고/박스 요약 (수동 보정 메모)</span>
@@ -66,8 +57,8 @@
         <textarea class="erp-input" name="memo" rows="2">{{ shipment.memo if shipment else '' }}</textarea></label>
     </div>
 
-    <!-- ── 품목 라인 ── -->
-    <div class="erp-card cpg-form-card">
+    <!-- ── 품목 라인 (오른쪽) ── -->
+    <div class="erp-card cpg-form-card cpg-form-lines">
       <div class="cpg-card-head">
         <h2>품목 라인</h2>
         <span class="erp-muted">
@@ -90,6 +81,8 @@
       <button type="button" class="erp-btn erp-btn-outline" id="cpg-add-line">+ 라인 추가</button>
     </div>
 
+    </div><!-- /cpg-form-2col -->
+
     <div class="erp-page-actions">
       <button type="submit" class="erp-btn erp-btn-primary">저장</button>
       {% if mode == 'edit' %}