Show finished sub-agent durations only and fix related tests

Drop live Date.now() duration from running strip labels so formatSessionLabel
stays deterministic. Update chrome-zone StatusBar props and agents-strip
expectations for finishedAt durations.

Author: TheGreatAxios

src/tui/components/agents-strip.tsx

@@ -314,12 +314,12 @@ function currentToolArguments(session: SubAgentSession): string {
 }
 
 export function formatSessionLabel(session: SubAgentSession): string {
+  // Only finished workers get a duration suffix — matches status-bar policy
+  // (completed sub-agent times, not a live tick for in-flight sessions).
   const duration =
     session.finishedAt !== undefined && session.finishedAt >= session.startedAt
       ? formatStripDuration(session.finishedAt - session.startedAt)
-      : session.status === "running"
-        ? formatStripDuration(Date.now() - session.startedAt)
-        : undefined;
+      : undefined;
   const durationSuffix = duration !== undefined ? ` · ${duration}` : "";
   if (session.status === "running" && session.currentToolName !== null) {
     const args = currentToolArguments(session);

tests/unit/tui/agents-strip.test.ts

@@ -258,8 +258,9 @@ describe("formatSessionLabel", () => {
       status: "done",
       currentToolName: null,
       toolNames: ["grep", "read_file"],
+      finishedAt: 5_000,
     });
-    expect(formatSessionLabel(session)).toBe("researcher: researching things · 2 tools");
+    expect(formatSessionLabel(session)).toBe("researcher: researching things · 2 tools · 5s");
   });
 
   test("shell tool preview leads with the command, not a redundant tool name", () => {
@@ -269,6 +270,15 @@ describe("formatSessionLabel", () => {
     const session = baseSession({ currentToolName: "run_shell", entries });
     expect(formatSessionLabel(session)).toBe("researcher: researching things — bun test");
   });
+
+  test("appends finished duration when finishedAt is set", () => {
+    const session = baseSession({
+      status: "done",
+      currentToolName: null,
+      finishedAt: 65_000,
+    });
+    expect(formatSessionLabel(session)).toBe("researcher: researching things · 1m 5s");
+  });
 });
 
 describe("agentsStripRowColor", () => {

tests/unit/tui/chrome-zone-budgets.test.tsx

@@ -35,7 +35,7 @@ test("status budget matches the rows StatusBar paints inside App's marginTop wra
   // App wraps StatusBar in <Box marginTop={1}>; mirror that wrapper here.
   const { lastFrame } = render(
     <Box marginTop={1}>
-      <StatusBar sessionElapsedMs={0} mcpCount={0} />
+      <StatusBar mcpCount={0} />
     </Box>,
   );
   expect(frameRows(lastFrame())).toBe(CHROME_ZONE_ROWS.status);