style(ui): 统一底部操作栏按钮间距，取消所有gap样式

- 移除各底部操作栏（footer/__actions/page-actions）内所有gap属性
- 按钮间距统一采用 Element Plus 全局默认的相邻按钮12px margin-left规则
- 修改 .el-dialog__footer 内.el-button间距由8px调整为12px，保持全站一致
- 确认 Avue 表单底部按钮无自带间距，去gap后间距由 Element Plus 提供
- 涉及模块覆盖 vehicle、payment、business、settlement，移除了相关组件样式中gap属性
- MEMORY.md规范更新，补充底栏按钮间距统一为无gap纯文字规则

src/styles/element-ui.scss

@@ -194,7 +194,7 @@
   border-radius: 0 0 var(--el-dialog-border-radius, 4px);
 
   .el-button + .el-button {
-    margin-left: 8px;
+    margin-left: 12px;
   }
 }
 

src/views/business/components/business-crud-page.vue

@@ -15311,7 +15311,6 @@ export default {
   display: flex;
   align-items: center;
   justify-content: flex-end;
-  gap: 8px;
   min-height: 64px;
   box-sizing: border-box;
   padding: 12px 24px;

src/views/business/components/master-order-dispatch.vue

@@ -705,7 +705,7 @@ export default {
 .freight-form { :deep(.freight-unit-select) { width: 92px; flex: 0 0 92px; min-width: 0; } }
 .carrier-type-form { margin-top: 16px; }
 .carrier-form { padding-top: 8px; }
-.segment-actions { display: flex; justify-content: flex-end; gap: 12px; padding-top: 4px; }
+.segment-actions { display: flex; justify-content: flex-end; padding-top: 4px; }
 .dispatch-bottom { position: fixed; z-index: 10; bottom: 0; left: $sidebar_width; width: calc(100% - #{$sidebar_width}); border-top: 1px solid #eff1f7; background: #fff; box-shadow: 0 -2px 8px rgba(0, 0, 0, 0.04); }
 :global(.avue--collapse) .dispatch-bottom { left: $sidebar_collapse; width: calc(100% - #{$sidebar_collapse}); }
 :global(.avue-layout--horizontal) .dispatch-bottom { left: 0; width: 100%; }
@@ -714,7 +714,7 @@ export default {
 .pending-summary, .pending-actions { display: flex; align-items: center; }
 .pending-summary { gap: 16px; }
 .pending-summary-text { color: #606266; font-weight: 400; }
-.pending-actions { gap: 12px; margin-left: auto; }
+.pending-actions { margin-left: auto; }
 .pending-list { max-height: min(420px, calc(100vh - 130px)); padding: 0 32px 16px; overflow: auto; h3 { margin: 14px 0 10px; font-size: 14px; } }
 .table-actions { display: flex; flex-wrap: wrap; gap: 8px; }
 @media screen and (max-width: 1200px) { .overview-content { grid-template-columns: 1fr; } .route-overview { justify-content: flex-start; } }

src/views/business/components/master-order-editor.vue

@@ -2050,7 +2050,6 @@ export default {
 footer {
   display: flex;
   justify-content: flex-end;
-  gap: 12px;
   padding: 12px 24px;
   position: fixed;
   right: 0;

src/views/business/project-apply.vue

@@ -2281,7 +2281,6 @@ export default {
 .project-apply-dialog__footer {
   display: flex;
   justify-content: flex-end;
-  gap: 8px;
 
   .project-apply-page-form & {
     position: fixed;

src/views/payment/bill-ledger-form.vue

@@ -592,7 +592,6 @@ export default {
 .bill-ledger-form-page__actions {
   display: flex;
   justify-content: flex-end;
-  gap: 12px;
   padding: 12px 24px;
   position: fixed;
   right: 0;

src/views/payment/bill-payment-form.vue

@@ -399,7 +399,6 @@ export default {
 .bill-payment-form-page__actions {
   display: flex;
   justify-content: flex-end;
-  gap: 12px;
   padding: 12px 24px;
   position: fixed;
   right: 0;

src/views/payment/invoice-application-form.vue

@@ -980,7 +980,6 @@ export default {
 .invoice-form-page__actions {
   display: flex;
   justify-content: flex-end;
-  gap: 12px;
   padding: 12px 24px;
   position: fixed;
   right: 0;

src/views/payment/invoice-receipt-form.vue

@@ -777,7 +777,6 @@ export default {
 .receipt-form-page__actions {
   display: flex;
   justify-content: flex-end;
-  gap: 12px;
   padding: 12px 24px;
   position: fixed;
   right: 0;

src/views/payment/payment-application-form.vue

@@ -1283,7 +1283,6 @@ export default {
 .payment-form-page__actions {
   display: flex;
   justify-content: flex-end;
-  gap: 12px;
   padding: 12px 24px;
   position: fixed;
   right: 0;

src/views/payment/receipt-claim-record-form.vue

@@ -313,7 +313,6 @@ export default {
 .claim-record-form-page__actions {
   display: flex;
   justify-content: flex-end;
-  gap: 12px;
   padding: 12px 24px;
   position: fixed;
   right: 0;

src/views/payment/receipt-flow-form.vue

@@ -472,7 +472,6 @@ export default {
 .receipt-claim-form-page__actions {
   display: flex;
   justify-content: flex-end;
-  gap: 12px;
   padding: 12px 24px;
   position: fixed;
   right: 0;

src/views/settlement/components/formal-settlement-editor.vue

@@ -1548,7 +1548,6 @@ export default {
   justify-content: flex-end;
   padding: 12px 24px;
   border-top: 1px solid #eff1f7;
-  gap: 12px;
   position: fixed;
   right: 0;
   left: 230px;

src/views/settlement/components/pre-settlement-editor.vue

@@ -1531,7 +1531,6 @@ export default {
     justify-content: flex-end;
     padding: 12px 24px;
     border-top: 1px solid #eff1f7;
-    gap: 12px;
     position: fixed;
     right: 0;
     left: 230px;

src/views/settlement/receivable-payable-detail.vue

@@ -1841,7 +1841,6 @@ export default {
   display: flex;
   flex-wrap: wrap;
   justify-content: center;
-  gap: 8px;
 }
 
 .settlement-detail-page__pagination {

src/views/vehicle/customer-archive.vue

@@ -5063,7 +5063,6 @@ export default {
 .archive-form__footer {
   display: flex;
   justify-content: flex-end;
-  gap: 12px;
   .archive-page-form & {
     position: fixed;
     right: 0;