支持结账多轮协商与按实际消耗双比例结算

允许双方最多 6 轮修改结账方案；哈夫币按实际消耗与 buyer/seller 比例计价，打超从押金扣，押金不足禁止自动完结并引导人工争议。同步收紧结账明细展示密度。

frontend/src/features/orders/views/OrderDetailView.vue

@@ -72,6 +72,11 @@ const {
   ownerIncomeLabel,
   canOpenDispute,
   canCancelDispute,
+  canCounterCheckout,
+  canAcceptCheckoutProposal,
+  checkoutShortfallCent,
+  checkoutOvershootCent,
+  checkoutRoundLabel,
   isCheckoutDisputeStage,
   handleCancel,
   handlePay,
@@ -129,6 +134,13 @@ const hasSidebarActions = computed(() => {
     (isRenter.value && order.value.status === 'pending_checkout_accept')
   )
 })
+const showCheckoutCounterForm = computed(
+  () =>
+    !!order.value &&
+    canCounterCheckout.value &&
+    ((isOwner.value && order.value.status === 'pending_checkout_confirm') ||
+      (isRenter.value && order.value.status === 'pending_checkout_accept'))
+)
 const disputeSupportTitle = computed(() => {
   if (canCancelDispute.value) {
     return order.value?.status === 'checkout_disputing' ? '结账争议处理中' : '申诉处理中'
@@ -480,15 +492,23 @@ watch([() => route.query.focus, order, loading], () => {
           :is-renter="isRenter"
         />
 
-        <div
-          v-if="order && isOwner && order.status === 'pending_checkout_confirm'"
-          class="form-section counter-checkout-section"
-        >
+        <div v-if="showCheckoutCounterForm" class="form-section counter-checkout-section">
           <div class="section-header">
-            <h2>修改结账</h2>
+            <h2>修改结账方案</h2>
+            <span v-if="checkoutRoundLabel">{{ checkoutRoundLabel }}</span>
           </div>
           <div class="form-card">
-            <h3 class="sub-title">修改结账金额</h3>
+            <p class="form-hint">
+              双方最多协商 6 轮。可填写<strong>实际哈夫币消耗</strong>（允许超过发布量）。
+              押金不足时无法自动完结，需改方案或发起争议。
+            </p>
+            <p v-if="checkoutShortfallCent > 0" class="form-hint" style="color: #dc2626">
+              当前方案押金不足差额 ¥{{ money(amountYuan(checkoutShortfallCent)) }}，无法同意完结。
+            </p>
+            <p v-else-if="checkoutOvershootCent > 0" class="form-hint">
+              当前打超 ¥{{ money(amountYuan(checkoutOvershootCent)) }}，将从押金扣除。
+            </p>
+            <h3 class="sub-title">调整消耗与扣款</h3>
             <el-form class="form-grid" label-position="top">
               <el-form-item label="额外消耗品已用金额">
                 <el-input-number
@@ -499,7 +519,7 @@ watch([() => route.query.focus, order, loading], () => {
                   controls-position="right"
                 />
               </el-form-item>
-              <el-form-item label="消耗哈夫币（M）">
+              <el-form-item label="实际消耗哈夫币（M）">
                 <el-input-number
                   v-model="counterForm.coin_consumed_m"
                   class="full-control"
@@ -508,12 +528,11 @@ watch([() => route.query.focus, order, loading], () => {
                   controls-position="right"
                 />
               </el-form-item>
-              <el-form-item label="押金赔付扣除（元）">
+              <el-form-item label="押金赔付扣除（损坏/违规，元）">
                 <el-input-number
                   v-model="counterForm.depositDeductAmountYuan"
                   class="full-control"
                   :min="0"
-                  :max="amountYuan(order.deposit_amount_cent)"
                   :precision="0"
                   controls-position="right"
                 />
@@ -523,7 +542,7 @@ watch([() => route.query.focus, order, loading], () => {
               v-model="counterForm.reason"
               type="textarea"
               :rows="3"
-              placeholder="填写修改原因"
+              placeholder="填写修改原因（必填）"
             />
             <el-input
               v-model="counterForm.evidenceText"
@@ -536,8 +555,9 @@ watch([() => route.query.focus, order, loading], () => {
               size="large"
               :loading="countering"
               @click="handleCounterCheckout"
-              >提交修正给租客确认</el-button
             >
+              {{ isOwner ? '提交修正给租客' : '提交还价给号主' }}
+            </el-button>
           </div>
         </div>
 
@@ -546,10 +566,12 @@ watch([() => route.query.focus, order, loading], () => {
           class="form-section reject-checkout-section"
         >
           <div class="section-header">
-            <h2>拒绝修正</h2>
+            <h2>不同意并发起争议</h2>
           </div>
           <div class="form-card">
-            <p class="form-hint">不同意修正时填写原因，订单会进入争议处理。</p>
+            <p class="form-hint">
+              也可先在上方「修改结账方案」还价。若谈不拢或押金不足，填写原因进入人工争议。
+            </p>
             <el-input
               v-model="rejectReason"
               type="textarea"
@@ -562,7 +584,7 @@ watch([() => route.query.focus, order, loading], () => {
               size="large"
               :loading="rejectingCheckout"
               @click="handleRejectCheckout"
-              >拒绝修正并发起争议</el-button
+              >发起结账争议</el-button
             >
           </div>
         </div>
@@ -576,41 +598,69 @@ watch([() => route.query.focus, order, loading], () => {
         <!-- 确认结账 -->
         <div v-if="isOwner && order.status === 'pending_checkout_confirm'" class="sidebar-card">
           <h3 class="sidebar-title">确认结账</h3>
+          <p v-if="checkoutRoundLabel" class="sidebar-hint">{{ checkoutRoundLabel }}</p>
+          <p v-if="checkoutShortfallCent > 0" class="sidebar-hint" style="color: #dc2626">
+            押金不足，无法同意完结
+          </p>
           <el-button
             type="primary"
             size="large"
             :loading="completing"
+            :disabled="!canAcceptCheckoutProposal"
             @click="handleConfirmCheckout"
           >
             确认结账并完成订单
           </el-button>
-          <div class="section-divider-mini">
+          <div v-if="canCounterCheckout" class="section-divider-mini">
             <span>或者</span>
           </div>
-          <el-button type="warning" plain size="large" @click="scrollToCounterCheckout">
-            需要修改结账金额
+          <el-button
+            v-if="canCounterCheckout"
+            type="warning"
+            plain
+            size="large"
+            @click="scrollToCounterCheckout"
+          >
+            修改结账方案
           </el-button>
-          <p class="sidebar-hint">如认为金额有误，点击上方按钮修改</p>
+          <p class="sidebar-hint">双方可多轮协商（最多 6 轮）；押金不足请改方案或争议</p>
         </div>
 
         <!-- 确认修正结账 -->
         <div v-if="isRenter && order.status === 'pending_checkout_accept'" class="sidebar-card">
-          <h3 class="sidebar-title">确认修正结账</h3>
+          <h3 class="sidebar-title">确认结账方案</h3>
+          <p v-if="checkoutRoundLabel" class="sidebar-hint">{{ checkoutRoundLabel }}</p>
+          <p v-if="checkoutShortfallCent > 0" class="sidebar-hint" style="color: #dc2626">
+            押金不足，无法同意完结
+          </p>
           <el-button
             type="primary"
             size="large"
             :loading="acceptingCheckout"
+            :disabled="!canAcceptCheckoutProposal"
             @click="handleAcceptCheckout"
           >
-            同意修正并完成订单
+            同意并完成订单
+          </el-button>
+          <div v-if="canCounterCheckout" class="section-divider-mini">
+            <span>或者</span>
+          </div>
+          <el-button
+            v-if="canCounterCheckout"
+            type="warning"
+            plain
+            size="large"
+            @click="scrollToCounterCheckout"
+          >
+            还价修改方案
           </el-button>
           <div class="section-divider-mini">
             <span>或者</span>
           </div>
           <el-button type="danger" plain size="large" @click="scrollToRejectCheckout">
-            不同意，发起争议
+            发起争议（人工）
           </el-button>
-          <p class="sidebar-hint">不同意修正时需填写原因，将进入争议处理</p>
+          <p class="sidebar-hint">可还价或争议；押金不足无法自动完结</p>
         </div>
       </div>
     </div>