fix(agents): drop the running tool's name from the working row

The tool in progress already shows as the last card of the conversation, and
next to it the row's elapsed time read as that tool's duration rather than the
turn's. The row now shows Working… with the turn's elapsed time, and still
shows retries and the starting state.

src/features/agents/Session.module.css

@@ -1546,12 +1546,6 @@
 .planCurrent {
   color: var(--fg);
 }
-.trayActivity {
-  min-width: 0;
-  overflow: hidden;
-  text-overflow: ellipsis;
-  white-space: nowrap;
-}
 /* A one-button toolbar, not a round bubble: the popup's large arc would turn it into a circle. */
 .quotePopup {
   display: flex;

src/features/agents/SessionEditor.tsx

@@ -75,7 +75,7 @@ import { ConfigPickers } from "./ConfigPickers";
 import { findRanges, formatDuration, formatSentAt } from "./conversation";
 import { ImagePreview, imageSrc } from "./ImagePreview";
 import { useAgentSettings } from "./agentSettings";
-import { currentTool, foldedTurns, summarizeWork, workParts, type FoldedTurn, type WorkSummary } from "./timeline";
+import { foldedTurns, summarizeWork, workParts, type FoldedTurn, type WorkSummary } from "./timeline";
 import { useRevealedText } from "./reveal";
 import { AgentReply, MessageActions, ReplyActions } from "./AgentReply";
 import {
@@ -2388,7 +2388,6 @@ function Tray({
   const added = changes?.reduce((n, c) => n + c.added, 0) ?? 0;
   const removed = changes?.reduce((n, c) => n + c.removed, 0) ?? 0;
   const busy = task.status === "running" || task.status === "starting";
-  const tool = entries && busy ? currentTool(entries) : null;
   const lastUser = entries?.findLast((e): e is UserEntry => e.type === "user");
   return (
     <div className={styles.tray}>
@@ -2445,10 +2444,6 @@ function Tray({
           <Spinner size={12} />
           {task.retry ? (
             <Retrying retry={task.retry} />
-          ) : tool ? (
-            <span className={styles.trayActivity} title={tool.title}>
-              {shortTitle(task, tool.title || tool.kind)}
-            </span>
           ) : (
             <T>{task.status === "starting" ? "Starting the agent…" : "Working…"}</T>
           )}

src/features/agents/timeline.test.ts

@@ -1,6 +1,6 @@
 import { describe, expect, it } from "vitest";
 import type { AgentEntry } from "@/bindings";
-import { currentTool, foldedTurns, summarizeWork, workParts } from "./timeline";
+import { foldedTurns, summarizeWork, workParts } from "./timeline";
 
 const user = (text: string, extra: Partial<Extract<AgentEntry, { type: "user" }>> = {}): AgentEntry => ({
   type: "user",
@@ -45,11 +45,6 @@ describe("summarizeWork", () => {
       { text: "1 other tool call", count: 1 },
     ]);
   });
-
-  it("finds the call in progress", () => {
-    expect(currentTool([tool("read", { status: "running" }), tool("search")])?.kind).toBe("read");
-    expect(currentTool([tool("read")])).toBeNull();
-  });
 });
 
 describe("foldedTurns", () => {

src/features/agents/timeline.ts

@@ -91,15 +91,6 @@ export function workParts(s: WorkSummary): Array<{ text: string; count: number }
   return parts.filter(([, , n]) => n > 0).map(([one, many, count]) => ({ text: count === 1 ? one : many, count }));
 }
 
-/** The running tool call of a run, if any: what the agent is doing right now. */
-export function currentTool(entries: readonly AgentEntry[]): ToolEntry | null {
-  for (let i = entries.length - 1; i >= 0; i--) {
-    const e = entries[i]!;
-    if (e.type === "tool" && (e.status === "running" || e.status === "pending")) return e;
-  }
-  return null;
-}
-
 /** A finished turn: the message that asked it at `user`, its work in `[user + 1, reply)`. */
 export interface FoldedTurn {
   user: number;