feat(FN-2685): remove TaskCard token usage badge

- Remove token usage badge rendering and compact token formatting from TaskCard
- Drop token usage fields from TaskCard memo equality checks now that the badge is gone
- Delete obsolete TaskCard token badge CSS rules and icon import
- Simplify TaskCard tests by removing token badge assertions and related fixtures

packages/dashboard/app/components/TaskCard.css

@@ -478,21 +478,6 @@
   opacity: 0.7;
 }
 
-.card-token-usage {
-  display: inline-flex;
-  align-items: center;
-  gap: var(--space-xs);
-  color: var(--text-muted);
-  font-size: calc(var(--space-sm) + var(--space-xs) * 0.75);
-  line-height: 1;
-  white-space: nowrap;
-}
-
-.card-token-usage-value {
-  font-family: var(--font-mono);
-  font-weight: 600;
-}
-
 .card-time-indicator {
   display: inline-flex;
   align-items: center;
@@ -1004,10 +989,6 @@
     gap: var(--space-xs);
   }
 
-  .card-token-usage {
-    font-size: calc(var(--space-sm) + var(--space-xs) * 0.5);
-  }
-
   .card-time-indicator {
     padding: var(--space-xs) var(--space-sm);
     font-size: 10px;

packages/dashboard/app/components/TaskCard.tsx

@@ -1,6 +1,6 @@
 import "./TaskCard.css";
 import { memo, useCallback, useState, useRef, useEffect, useMemo } from "react";
-import { Link, Clock, Layers, Pencil, ChevronDown, Folder, Target, Bot, Trash2, Zap } from "lucide-react";
+import { Link, Clock, Layers, Pencil, ChevronDown, Folder, Target, Bot, Trash2 } from "lucide-react";
 import type { Task, TaskDetail, Column, PrInfo, IssueInfo, TaskPriority } from "@fusion/core";
 import { COLUMN_LABELS, DEFAULT_TASK_PRIORITY, TASK_PRIORITIES, VALID_TRANSITIONS, getErrorMessage } from "@fusion/core";
 import { fetchTaskDetail, uploadAttachment, fetchMission, fetchAgent } from "../api";
@@ -165,23 +165,6 @@ function formatElapsedDuration(elapsedMs: number): string {
   return `${elapsedDays}d`;
 }
 
-function formatCompactTokenCount(value: number): string {
-  if (!Number.isFinite(value) || value < 0) {
-    return "0";
-  }
-
-  if (value < 1_000) {
-    return String(value);
-  }
-
-  const trimTrailingDecimal = (formatted: string) => formatted.replace(/\.0$/, "");
-
-  if (value < 1_000_000) {
-    return `${trimTrailingDecimal((value / 1_000).toFixed(1))}k`;
-  }
-
-  return `${trimTrailingDecimal((value / 1_000_000).toFixed(1))}M`;
-}
 
 interface TaskCardProps {
   task: Task;
@@ -371,8 +354,6 @@ function areTaskCardPropsEqual(previous: TaskCardProps, next: TaskCardProps): bo
     previousTask.missionId === nextTask.missionId &&
     previousTask.assignedAgentId === nextTask.assignedAgentId &&
     previousTask.mergeRetries === nextTask.mergeRetries &&
-    previousTask.tokenUsage?.totalTokens === nextTask.tokenUsage?.totalTokens &&
-    previousTask.tokenUsage?.lastUsedAt === nextTask.tokenUsage?.lastUsedAt &&
     areAttachmentsEqual(previousTask.attachments, nextTask.attachments) &&
     areCommentsEqual(previousTask.comments, nextTask.comments) &&
     areTaskDependenciesEqual(previousTask.dependencies, nextTask.dependencies) &&
@@ -1131,18 +1112,6 @@ function TaskCardComponent({
     return null;
   })();
 
-  const tokenUsageIndicator = task.tokenUsage ? (
-    <span
-      className="card-token-usage"
-      title={`${task.tokenUsage.totalTokens.toLocaleString()} tokens`}
-      aria-label={`Token usage ${formatCompactTokenCount(task.tokenUsage.totalTokens)} tokens`}
-    >
-      <Zap size={12} />
-      <span className="card-token-usage-value">{formatCompactTokenCount(task.tokenUsage.totalTokens)}</span>
-      <span>tokens</span>
-    </span>
-  ) : null;
-
   if (isEditing) {
     return (
       <div
@@ -1415,10 +1384,9 @@ function TaskCardComponent({
           </>
         );
       })()}
-      {(filesChangedButton || timeIndicator || tokenUsageIndicator) && (
+      {(filesChangedButton || timeIndicator) && (
         <div className="card-footer-row">
           {filesChangedButton}
-          {tokenUsageIndicator}
           {timeIndicator && (
             <span
               className="card-time-indicator"

packages/dashboard/app/components/__tests__/TaskCard.test.tsx

@@ -1,6 +1,6 @@
 import { afterEach, describe, it, expect, vi } from "vitest";
 import { render, screen, fireEvent, waitFor, act } from "@testing-library/react";
-import { TaskCard, __test_areTaskCardPropsEqual } from "../TaskCard";
+import { TaskCard } from "../TaskCard";
 import type { Task } from "@fusion/core";
 
 // Mock lucide-react to avoid SVG rendering issues in test env
@@ -16,7 +16,6 @@ vi.mock("lucide-react", () => ({
   Target: () => null,
   Bot: () => null,
   Trash2: () => null,
-  Zap: () => null,
 }));
 
 vi.mock("../ProviderIcon", () => ({
@@ -48,15 +47,6 @@ function makeTask(overrides: Partial<Task> = {}): Task {
 
 const noop = () => {};
 
-const tokenUsageFixture = {
-  inputTokens: 50_000,
-  outputTokens: 30_000,
-  cachedTokens: 10_000,
-  totalTokens: 90_000,
-  firstUsedAt: "2026-04-26T10:00:00.000Z",
-  lastUsedAt: "2026-04-26T10:30:00.000Z",
-} as const;
-
 afterEach(() => {
   vi.useRealTimers();
 });
@@ -67,33 +57,6 @@ describe("TaskCard", () => {
     expect(screen.getByText("FN-001")).toBeDefined();
   });
 
-  it("renders token usage indicator when task has token usage", () => {
-    const { container } = render(
-      <TaskCard
-        task={makeTask({ tokenUsage: { ...tokenUsageFixture } })}
-        onOpenDetail={noop}
-        addToast={noop}
-      />,
-    );
-
-    const tokenUsage = container.querySelector(".card-token-usage");
-    expect(tokenUsage).not.toBeNull();
-    expect(tokenUsage?.textContent).toContain("90k");
-    expect(tokenUsage?.textContent).toContain("tokens");
-  });
-
-  it("does not render token usage indicator when tokenUsage is undefined", () => {
-    const { container } = render(
-      <TaskCard
-        task={makeTask({ tokenUsage: undefined })}
-        onOpenDetail={noop}
-        addToast={noop}
-      />,
-    );
-
-    expect(container.querySelector(".card-token-usage")).toBeNull();
-  });
-
   it("renders the status badge when task.status is set", () => {
     render(
       <TaskCard
@@ -740,32 +703,6 @@ describe("TaskCard", () => {
   });
 });
 
-describe("TaskCard memo comparator", () => {
-  it("detects token usage changes", () => {
-    type ComparatorProps = Parameters<typeof __test_areTaskCardPropsEqual>[0];
-
-    const baseTask = makeTask({ tokenUsage: { ...tokenUsageFixture } });
-    const baseProps: ComparatorProps = {
-      task: baseTask,
-      onOpenDetail: noop,
-      addToast: noop,
-    };
-
-    const totalTokenChange: ComparatorProps = {
-      ...baseProps,
-      task: makeTask({ tokenUsage: { ...tokenUsageFixture, totalTokens: 95_000 } }),
-    };
-
-    const lastUsedAtChange: ComparatorProps = {
-      ...baseProps,
-      task: makeTask({ tokenUsage: { ...tokenUsageFixture, lastUsedAt: "2026-04-26T10:35:00.000Z" } }),
-    };
-
-    expect(__test_areTaskCardPropsEqual(baseProps, totalTokenChange)).toBe(false);
-    expect(__test_areTaskCardPropsEqual(baseProps, lastUsedAtChange)).toBe(false);
-  });
-});
-
 describe("TaskCard provider icons on agent row", () => {
   it("renders provider icons when task has model overrides", () => {
     render(