Remove scrollbars from plan position cards.

Let position cards size to content instead of clipping with overflow-y auto.

Co-authored-by: Cursor <cursoragent@cursor.com>

frontend/src/styles/app.css

@@ -1086,7 +1086,7 @@ input {
   }
 }
 
-/* 计划页：上排策略|持仓等高（取两边较高）；内容溢出时卡片内滚动 */
+/* 计划页：上排策略|持仓等高（取两边较高）；持仓卡片按内容撑开，不出现内滚动条 */
 .plan-shell {
   --plan-cols: minmax(0, 1fr) minmax(0, 1.15fr);
   --plan-gap: 12px;
@@ -1114,7 +1114,6 @@ input {
 
 .plan-board > * {
   min-width: 0;
-  min-height: 0;
 }
 
 .plan-panel-title {
@@ -1156,28 +1155,24 @@ input {
   flex-direction: column;
   gap: var(--plan-gap);
   height: 100%;
-  min-height: 0;
   min-width: 0;
   width: 100%;
 }
 
 .plan-positions .pos-card,
 .plan-positions .pos-empty {
-  flex: 1 1 0;
+  flex: 1 1 auto;
   display: flex;
   flex-direction: column;
   justify-content: center;
-  min-height: 0;
   min-width: 0;
   width: 100%;
   box-sizing: border-box;
-  overflow: hidden;
+  overflow: visible;
 }
 
 .plan-positions .pos-card {
   justify-content: flex-start;
-  overflow-x: hidden;
-  overflow-y: auto;
 }
 
 .pos-countdown {
@@ -1220,7 +1215,6 @@ input {
   .plan-positions .pos-card,
   .plan-positions .pos-empty {
     flex: 0 0 auto;
-    overflow: visible;
   }
 
   /* 合约名与倒计时上下排，避免长 inst_id 被挤成竖排 */