Fix drift sync: per-window verdicts, forgiving class match, event-driven status bar

Three independent defects made the focus state feel flaky and let the OS
status bar disagree with the web UI:

- Status file lagged the web by up to a minute: it rendered only on a 60s
  ticker with no hook into state changes. notify() now fans out to multiple
  listeners (AddOnChange) and the writer has a coalesced Wake() so drift
  reaches the bar as promptly as the browser.

- A brief off-task visit could latch drift for the whole session. Sibling
  windows of one app (a browser's reading tab vs its chat tab) share a window
  class, but the judge verdict was cached by class alone, so one tab's verdict
  poisoned the rest and never re-judged. Cache is now keyed by class + scrubbed
  title (judgedWindows) so siblings are judged independently.

- Allowed-class matching was exact equality, so a short token ("brave") never
  matched the real WM_CLASS ("Brave-browser") and every window was routed to
  the LLM. Matching is now substring-based, and planning surfaces the live
  window class with a click-to-add chip so users pick a token that matches.

Also fix the planning checkbox alignment: the global full-width input rule was
stretching the "Enforce focus" checkbox; scope it out for checkboxes.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

internal/session/session_test.go

@@ -386,6 +386,29 @@ func TestStartCommitmentPersistsAllowedClasses(t *testing.T) {
 	}
 }
 
+func TestPlanningStateExposesCurrentWindowClass(t *testing.T) {
+	c, _ := newTestController(t)
+	c.RecordWindow(obs("Brave-browser", "Consume - Brave"))
+	if err := c.EnterPlanning(); err != nil {
+		t.Fatalf("planning: %v", err)
+	}
+	st := c.State()
+	if st.Evidence == nil || st.Evidence.Current.Class != "Brave-browser" {
+		t.Fatalf("planning should expose the live window class so the user can pick a matching token, got %+v", st.Evidence)
+	}
+}
+
+func TestAddOnChangeFansOutToAllListeners(t *testing.T) {
+	c, _ := newTestController(t)
+	var a, b int
+	c.SetOnChange(func() { a++ })
+	c.AddOnChange(func() { b++ })
+	c.notify()
+	if a != 1 || b != 1 {
+		t.Fatalf("every registered listener should fire: a=%d b=%d", a, b)
+	}
+}
+
 func TestOnTaskAppendsCurrentClass(t *testing.T) {
 	c, _ := newTestController(t)
 	_ = c.EnterPlanning()
@@ -478,7 +501,54 @@ func TestUnmatchedWindowIsJudgedDrifting(t *testing.T) {
 	}
 }
 
-func TestPerClassCacheAvoidsSecondJudge(t *testing.T) {
+// titleJudge returns a verdict chosen by which substring the title contains,
+// so a test can model an app (e.g. a browser) hosting both on- and off-task
+// windows under one window class.
+type titleJudge struct {
+	byTitle map[string]ai.Verdict
+	calls   int32
+}
+
+func (j *titleJudge) JudgeDrift(ctx context.Context, commitment, class, title string) (ai.Verdict, error) {
+	atomic.AddInt32(&j.calls, 1)
+	for sub, v := range j.byTitle {
+		if strings.Contains(title, sub) {
+			return v, nil
+		}
+	}
+	return ai.Verdict{OnTask: true}, nil
+}
+
+// A brief off-task window must not poison every later same-class window. Teams
+// and a Consume reading page are both class "Brave-browser"; caching the judge
+// verdict by class alone made the on-task page inherit Teams's drift verdict
+// (and never re-judge), latching drift for the rest of the session.
+func TestVerdictCacheKeysOnTitleNotClassAlone(t *testing.T) {
+	c, _ := newTestController(t)
+	now := time.Now()
+	c.SetClock(func() time.Time { return now })
+	fj := &titleJudge{byTitle: map[string]ai.Verdict{
+		"Teams":   {OnTask: false, Reason: "Teams is off-task"},
+		"Consume": {OnTask: true},
+	}}
+	c.SetDriftJudge(fj)
+	startActive(t, c, []string{"code"}) // Brave-browser never matches locally
+
+	c.RecordWindow(obs("Brave-browser", "Microsoft Teams - Brave"))
+	waitDriftStatus(t, c, "drifting")
+
+	now = now.Add(2 * driftDebounce) // clear debounce so a re-judge is allowed
+	c.RecordWindow(obs("Brave-browser", "Consume - Brave"))
+	st := waitDriftStatus(t, c, "ontask")
+	if st.Drift.Reason != "" {
+		t.Fatalf("on-task window must not carry the Teams reason: %+v", st.Drift)
+	}
+	if got := atomic.LoadInt32(&fj.calls); got != 2 {
+		t.Fatalf("different title under same class should re-judge, calls=%d", got)
+	}
+}
+
+func TestPerWindowCacheAvoidsSecondJudge(t *testing.T) {
 	c, _ := newTestController(t)
 	now := time.Now()
 	c.SetClock(func() time.Time { return now })
@@ -488,12 +558,13 @@ func TestPerClassCacheAvoidsSecondJudge(t *testing.T) {
 	c.RecordWindow(obs("firefox", "YouTube"))
 	waitDriftStatus(t, c, "drifting")
 	// Advance past the debounce window so a second judge call would be allowed:
-	// this isolates the per-class cache as the only reason the judge is skipped.
+	// this isolates the per-window cache as the only reason the judge is skipped.
 	now = now.Add(2 * driftDebounce)
-	c.RecordWindow(obs("firefox", "Reddit")) // same class, should hit cache
+	c.RecordWindow(obs("Code", "main.go"))    // switch away (local on-task match)
+	c.RecordWindow(obs("firefox", "YouTube")) // same window, should hit cache
 	time.Sleep(50 * time.Millisecond)
 	if got := atomic.LoadInt32(&fj.calls); got != 1 {
-		t.Fatalf("cached class should not re-judge, calls=%d", got)
+		t.Fatalf("cached window should not re-judge, calls=%d", got)
 	}
 }
 
@@ -554,7 +625,7 @@ func TestRestoredActiveSessionCanBeJudged(t *testing.T) {
 		t.Fatalf("reload: %v", err)
 	}
 	second.SetDriftJudge(&fakeJudge{verdict: ai.Verdict{OnTask: false, Reason: "off-task"}})
-	second.RecordWindow(obs("firefox", "YouTube")) // must not panic on nil judgedClasses map
+	second.RecordWindow(obs("firefox", "YouTube")) // must not panic on nil judgedWindows map
 	waitDriftStatus(t, second, "drifting")
 }
 
@@ -714,8 +785,8 @@ func TestNudgeDoesNotRunOnDriftPath(t *testing.T) {
 	c.SetDriftJudge(&fakeJudge{verdict: ai.Verdict{OnTask: false, Reason: "off-task"}})
 	startActive(t, c, []string{"code"})
 	c.RecordWindow(obs("firefox", "YouTube"))
-	c.RecordWindow(obs("firefox", "Reddit"))
 	waitDriftStatus(t, c, "drifting")
+	c.RecordWindow(obs("firefox", "Reddit")) // second off-task title builds nudge history
 	time.Sleep(50 * time.Millisecond)
 	if got := atomic.LoadInt32(&fn.calls); got != 0 {
 		t.Fatalf("nudge must not run on the drift path, calls=%d", got)
@@ -1484,7 +1555,8 @@ func TestRecordWindowCreditsSplitFaithfully(t *testing.T) {
 	waitDriftStatus(t, c, "drifting")          // wait for the async verdict before crediting the firefox segment
 
 	clk.advance(8 * time.Minute)
-	c.RecordWindow(snap("firefox", "Reddit")) // credits 8m to firefox/YouTube while drifting -> off-task; cache keeps drifting
+	c.RecordWindow(snap("firefox", "Reddit")) // credits 8m to firefox/YouTube while drifting -> off-task
+	waitDriftStatus(t, c, "drifting")         // Reddit is a distinct window: re-judged off-task before its segment is credited
 	clk.advance(4 * time.Minute)
 	if err := c.Complete(); err != nil { // flush: credits 4m to firefox/Reddit while drifting -> off-task
 		t.Fatalf("complete: %v", err)