feat(gui+ohos): 同步阶段管道工具格「只滚动展示最新一条调用」

WebUI 已改为工具格只露最新一条。桌面版与鸿蒙端是同一套运行态面板的
镜像，一并跟上，避免三端口径不一致：

- cmd/gui：renderRuntimePanel 工具格只渲染最新条目 + 本轮累计次数；
  overview 是整块 innerHTML 重建，故动画类由 state.toolFlash 单次驱动，
  避免任何重渲染都闪一下。
- cmd/ohos：RuntimePanel 工具格改为 latestEvent() + totalCount()，
  不再 ForEach 追加。已用 hvigor 实测 BUILD SUCCESSFUL。

cmd/gui/renderer/app.js

@@ -1094,6 +1094,10 @@ function rtTrailPush(g, kind, label, short) {
 function renderRuntimePanel() {
   var title = __("运行态", "Runtime");
   var rt = state.runtime;
+  // 工具格的滑入动画只在「新到一条工具调用」那一次播放：overview 是整块
+  // innerHTML 重建，节点每次都是新的；若无条件带动画类，任何重渲染都会闪一下。
+  var toolFlash = !!state.toolFlash;
+  state.toolFlash = false;
   if (!rt) {
     return (
       '<div class="card"><h2>' + title + '</h2><p class="rt-empty">' +
@@ -1133,22 +1137,44 @@ function renderRuntimePanel() {
     var items = (state.stageTrail || []).filter(function (t) {
       return (t.g | 0) === i;
     });
-    var body = items.length
-      ? items
-          .map(function (t) {
-            var kind = t.kind || "stage";
-            var ico =
-              kind === "output" ? RT_ICO.out : kind === "tool" ? RT_ICO.tool : "";
-            return (
-              '<span class="rt-chip rt-chip-' + kind + '" title="' +
-              escHtml(t.label) + '">' + ico +
-              escHtml(t.short || t.label) +
-              (t.n > 1 ? '<i class="rt-chip-n">x' + t.n + "</i>" : "") +
-              "</span>"
-            );
-          })
-          .join("")
-      : '<span class="rt-chip rt-chip-none">' + __("无", "none") + "</span>";
+    // 「工具」是循环格：一轮里可能调几十次工具/输出通道，全部追加会把这一格
+    // 撑成长条，反而看不出「现在在调什么」。只留**最新一条**，右侧给本轮累计
+    // 次数（与 WebUI 同一口径，见 internal/plugins/webui/dashboard.js）。
+    var cls = "rt-pipe-events";
+    var body;
+    if (!items.length) {
+      body = '<span class="rt-chip rt-chip-none">' + __("无", "none") + "</span>";
+    } else if (s.loop) {
+      cls += " rt-pipe-scroll";
+      var total = 0;
+      for (var k = 0; k < items.length; k++) total += items[k].n || 1;
+      var latest = items[items.length - 1];
+      var lkind = latest.kind || "stage";
+      var lico = lkind === "output" ? RT_ICO.out : lkind === "tool" ? RT_ICO.tool : "";
+      body =
+        '<span class="rt-chip rt-chip-' + lkind + (toolFlash ? " rt-chip-enter" : "") +
+        '" title="' + escHtml(latest.label) + '">' + lico +
+        '<b class="rt-chip-t">' + escHtml(latest.short || latest.label) + "</b>" +
+        (latest.n > 1 ? '<i class="rt-chip-n">x' + latest.n + "</i>" : "") +
+        "</span>" +
+        '<i class="rt-scroll-count" title="' +
+        __("本轮工具调用累计次数", "tool calls this turn") + '">x' + total + "</i>";
+    } else {
+      body = items
+        .map(function (t) {
+          var kind = t.kind || "stage";
+          var ico =
+            kind === "output" ? RT_ICO.out : kind === "tool" ? RT_ICO.tool : "";
+          return (
+            '<span class="rt-chip rt-chip-' + kind + '" title="' +
+            escHtml(t.label) + '">' + ico +
+            '<b class="rt-chip-t">' + escHtml(t.short || t.label) + "</b>" +
+            (t.n > 1 ? '<i class="rt-chip-n">x' + t.n + "</i>" : "") +
+            "</span>"
+          );
+        })
+        .join("");
+    }
     return (
       '<div class="rt-pipe-cell' + (i === g ? " active" : "") + '">' +
       '<div class="rt-pipe-head">' + RT_ICO[s.ico] +
@@ -1158,7 +1184,7 @@ function renderRuntimePanel() {
           __("工具调用会回到行动后，可多次", "tool calls loop back; may repeat") +
           '">' + RT_ICO.loop + "</em>"
         : "") +
-      '</div><div class="rt-pipe-events">' + body + "</div></div>"
+      '</div><div class="' + cls + '">' + body + "</div></div>"
     );
   }).join("");
   html += "</div>";
@@ -5477,6 +5503,7 @@ async function connectFetchSSE(url) {
                   tool,
                   rtShortTool(tool),
                 );
+              if (tool) state.toolFlash = true;
               state.chatStage = __("工具调用: ", "Tool: ") + (tool || "");
               if (tool && (state.pendingTools || []).indexOf(tool) === -1) {
                 if (!state.pendingTools) state.pendingTools = [];

cmd/gui/renderer/style.css

@@ -2287,6 +2287,40 @@ td .switch {
   gap: 4px;
   min-height: 23px;
 }
+/* 「工具」格的滚动视口：固定一行高，只露最新一条（与 WebUI 同一口径）。 */
+.rt-pipe-scroll {
+  flex-wrap: nowrap;
+  height: 23px;
+  min-height: 23px;
+  overflow: hidden;
+  align-items: center;
+}
+.rt-pipe-scroll .rt-chip {
+  flex: 0 1 auto;
+  min-width: 0;
+  max-width: none;
+}
+.rt-chip-enter {
+  animation: rt-chip-scroll-in 0.3s var(--ease-out);
+}
+@keyframes rt-chip-scroll-in {
+  from {
+    transform: translateY(115%);
+    opacity: 0;
+  }
+  to {
+    transform: translateY(0);
+    opacity: 1;
+  }
+}
+.rt-scroll-count {
+  flex: 0 0 auto;
+  margin-left: auto;
+  font-style: normal;
+  font-size: 10.5px;
+  opacity: 0.6;
+  font-variant-numeric: tabular-nums;
+}
 .rt-loop {
   display: inline-flex;
   color: var(--accent);
@@ -2308,6 +2342,13 @@ td .switch {
   border: 1px solid var(--border-color);
   color: var(--text-secondary);
 }
+.rt-chip-t {
+  font-weight: inherit;
+  min-width: 0;
+  overflow: hidden;
+  text-overflow: ellipsis;
+  white-space: nowrap;
+}
 .rt-chip-tool {
   border-color: rgba(136, 192, 208, 0.42);
   color: var(--frost-300);