feat(ui): aggregate the subagent strip when several runs are active

extensions/subagents/navigation.test.ts

@@ -113,7 +113,7 @@ test("subagent strip matches Workflow's bounded one-line affordance", () => {
   }
 });
 
-test("the metrics tail stays quiet while a run is healthy", () => {
+test("a lone subagent needs no count: glyph and name carry the state", () => {
   const strip = new BelowEditorStripState();
   const render = (status: SubagentSnapshot["status"]) => {
     const entry = selectSubagentStripEntry(
@@ -140,14 +140,38 @@ test("the metrics tail stays quiet while a run is healthy", () => {
     }
   };
 
-  // A routine run borrows no status colour in its tail: the coloured glyph on
-  // the left already carries the state, and hints recede furthest of all.
+  // One active subagent: the glyph and its name already say what a "1 running"
+  // count would repeat, and hints recede furthest of all.
   const running = render("running");
-  assert.match(running, /<muted>1 running<\/muted>/);
+  assert.match(running, /sa-1/);
+  assert.doesNotMatch(running, /1 running/);
   assert.match(running, /<dim>↓ to manage<\/dim>/);
-  assert.doesNotMatch(running, /<warning>1 running/);
 
-  // Once settled, the one count that carries the outcome takes the colour.
-  assert.match(render("error"), /<error>1 failed<\/error>/);
-  assert.match(render("done"), /<success>1 done<\/success>/);
+  // Once settled, the glyph takes the outcome's colour.
+  assert.match(render("error"), /<error>✗<\/error>/);
+  assert.match(render("done"), /<success>✓<\/success>/);
+});
+
+test("several active subagents aggregate instead of naming just one", () => {
+  const entry = selectSubagentStripEntry(
+    [
+      snapshot("sa-1", "running", Date.now() - 4_000),
+      snapshot("sa-2", "running", Date.now() - 2_000),
+    ],
+    0,
+  );
+  const widget = new SubagentStripWidget(
+    { requestRender() {} } as unknown as TUI,
+    markingTheme,
+    new BelowEditorStripState(),
+    () => entry,
+  );
+  try {
+    const rendered = widget.render(400)[0]!;
+    assert.match(rendered, /subagents/);
+    assert.match(rendered, /<muted>2 running<\/muted>/);
+    assert.doesNotMatch(rendered, /sa-1|sa-2/);
+  } finally {
+    widget.dispose();
+  }
 });

extensions/subagents/navigation.ts

@@ -106,20 +106,28 @@ export class SubagentStripWidget {
     const glyph = this.strip.focused
       ? this.theme.fg("accent", "❯")
       : statusGlyph(snapshot, this.theme, Date.now());
-    const titleText = normalizeSubagentTitle(snapshot.title, snapshot.id);
-    const title = this.strip.focused
-      ? this.theme.bold(this.theme.fg("accent", titleText))
-      : this.theme.fg("text", titleText);
+    // A name only means something when it names the only active subagent; with
+    // several, an aggregate label is honest and the counts carry the detail.
+    const total = counts.running + counts.done + counts.failed;
+    const single = total === 1;
+    const labelText = single
+      ? normalizeSubagentTitle(snapshot.title, snapshot.id)
+      : "subagents";
+    const label = this.strip.focused
+      ? this.theme.bold(this.theme.fg("accent", labelText))
+      : this.theme.fg("text", labelText);
     // The footer already shows the session model; the takeover view keeps the
     // per-subagent model, so the one-line strip stays title-only.
-    const left = ` ${glyph} ${title}`;
+    const left = ` ${glyph} ${label}`;
     // Worded counts read at a glance; the selected run's own state comes
-    // first so the emphasis colour always lands on the matching count.
+    // first so the emphasis colour always lands on the matching count. A lone
+    // subagent needs no count — the glyph and label already say it.
     const donePart = counts.done > 0 ? `${counts.done} done` : undefined;
     const failedPart =
       counts.failed > 0 ? `${counts.failed} failed` : undefined;
-    const activity =
-      counts.running > 0
+    const activity = single
+      ? []
+      : counts.running > 0
         ? [`${counts.running} running`]
         : snapshot.status === "error"
           ? [failedPart, donePart]
@@ -133,7 +141,9 @@ export class SubagentStripWidget {
         percent === undefined ? undefined : `${percent}% ctx`,
       ],
       this.strip.focused ? "enter open · ↑ back" : "↓ to manage",
-      snapshot.status === "running" ? undefined : statusColor(snapshot.status),
+      single || snapshot.status === "running"
+        ? undefined
+        : statusColor(snapshot.status),
     );
     return [fitNavigationSides(left, right, width)];
   }