Wire plan_ready, list_ready, new_suggestions and Send to Google Chat

Connect the features to the notification outbox so real events notify,
each stored by the new notify.EmitTx in the transaction of the change it
is about (Wake after commit):

- plan_ready:{weekStart} (/plan) when a draft job stores the AI's draft;
  a redraft shares the key and a manual swap never emits. The title reads
  "Next week's plan is ready" for the coming week.
- list_ready:{weekStart} (/plan/shopping) when a week's Supply run is
  first created, by generate or after Push to Calendar.
- new_suggestions:{batchId} (/discover) when a scheduled or manual batch
  ends done with cards; replenish batches never notify.
- plan.Service.EmitDayOfReminder(date) emits day_of_reminder:{date} for
  the Feature 20 scheduler.

Add POST /api/v1/shopping/{weekStart}/send-chat: shopping.SendToChat posts
the dinners with needed items and a link through chat.PostSupplyRun,
records sent_to_chat_at, and is idempotent per week unless
{"resend": true}. The Supply run's Send to Google Chat button calls it
("Send again" once sent) and shows failures in an ErrorBanner; the unused
Unavailable placeholder is removed.

Task: f0cd9d50-9c11-41be-a945-7bae9f5f28a4

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

internal/plan/plan_test.go

@@ -20,11 +20,14 @@ import (
 	"code.cubecraftlabs.com/Maniacs_Mansion/Meal-Quest/internal/ai/harness"
 	"code.cubecraftlabs.com/Maniacs_Mansion/Meal-Quest/internal/ai/llm"
 	"code.cubecraftlabs.com/Maniacs_Mansion/Meal-Quest/internal/ai/skills"
+	"code.cubecraftlabs.com/Maniacs_Mansion/Meal-Quest/internal/chat"
 	"code.cubecraftlabs.com/Maniacs_Mansion/Meal-Quest/internal/db"
 	"code.cubecraftlabs.com/Maniacs_Mansion/Meal-Quest/internal/gcal"
 	"code.cubecraftlabs.com/Maniacs_Mansion/Meal-Quest/internal/gcal/gcaltest"
 	"code.cubecraftlabs.com/Maniacs_Mansion/Meal-Quest/internal/household"
 	"code.cubecraftlabs.com/Maniacs_Mansion/Meal-Quest/internal/jobs"
+	"code.cubecraftlabs.com/Maniacs_Mansion/Meal-Quest/internal/notify"
+	"code.cubecraftlabs.com/Maniacs_Mansion/Meal-Quest/internal/notify/notifytest"
 	"code.cubecraftlabs.com/Maniacs_Mansion/Meal-Quest/internal/plan"
 	"code.cubecraftlabs.com/Maniacs_Mansion/Meal-Quest/internal/secretbox"
 	"code.cubecraftlabs.com/Maniacs_Mansion/Meal-Quest/internal/store"
@@ -143,7 +146,7 @@ func newEnv(t *testing.T) *env {
 	if err != nil {
 		t.Fatal(err)
 	}
-	e.svc, err = plan.NewService(st, drafter, e.runner, e.gcal, publicURL, logger)
+	e.svc, err = plan.NewService(st, drafter, e.runner, e.gcal, notifytest.New(t, st), publicURL, logger)
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -352,6 +355,85 @@ func TestDraftCreatesPlan(t *testing.T) {
 	}
 }
 
+// TestDraftEmitsPlanReady: the AI's first draft of a week stores plan_ready
+// keyed by the week, on push and Google Chat, naming the dinners Monday to
+// Sunday; a redraft (Rebuild week) and a manual swap store nothing more.
+func TestDraftEmitsPlanReady(t *testing.T) {
+	e := newEnv(t)
+	e.start(t)
+	e.reply("", fullWeek...)
+	e.mustDraft(t, false)
+
+	zone, err := time.LoadLocation("America/New_York")
+	if err != nil {
+		t.Fatal(err)
+	}
+	want := chat.PlanReady(week, household.WeekStart(household.Today(time.Now(), zone)), fullWeek)
+	rows := notifytest.Rows(t, e.st, notify.PlanReady)
+	if len(rows) != 2 || rows[0].Channel != notify.ChannelChat || rows[1].Channel != notify.ChannelPush {
+		t.Fatalf("plan_ready rows = %+v, want one on chat and one on push", rows)
+	}
+	for _, r := range rows {
+		p := r.Payload
+		if r.Key != "plan_ready:2026-10-12" || p.Tag != r.Key || p.URL != "/plan" || p.Week != "2026-10-12" ||
+			p.Title != want.Title || p.Body != "Beef Chili, Pot Roast, Pad Thai + 4 more" {
+			t.Errorf("%s row = %+v, want key plan_ready:2026-10-12, title %q, the drafted dinners and /plan", r.Channel, r, want.Title)
+		}
+	}
+
+	reversed := slices.Clone(fullWeek)
+	slices.Reverse(reversed)
+	e.reply("", reversed...)
+	e.mustDraft(t, false)
+	e.ids["Fish Tacos"] = e.dinner(t, "Fish Tacos", "regular", "stovetop", 25)
+	if _, err := e.svc.Swap(t.Context(), week, "2026-10-14", e.ids["Fish Tacos"]); err != nil {
+		t.Fatal(err)
+	}
+	if again := notifytest.Rows(t, e.st, notify.PlanReady); !slices.Equal(again, rows) {
+		t.Errorf("plan_ready rows after a redraft and a swap = %+v, want the first draft's only", again)
+	}
+}
+
+// TestFailedDraftEmitsNothing: a draft that stores no plan notifies no one.
+func TestFailedDraftEmitsNothing(t *testing.T) {
+	e := newEnv(t)
+	e.start(t)
+	e.model.QueueGenerate(llm.GenerateResult{Err: errors.New("provider down")})
+	if job := e.draft(t, false); job.Status != jobs.StatusFailed {
+		t.Fatalf("job %s, want failed", job.Status)
+	}
+	if rows := notifytest.Rows(t, e.st, notify.PlanReady); len(rows) != 0 {
+		t.Errorf("plan_ready rows = %+v, want none", rows)
+	}
+}
+
+// TestEmitDayOfReminder: the reminder of a planned date names its dinner,
+// keyed by the date; a date with no plan emits nothing, and a date emitted
+// again stores nothing more.
+func TestEmitDayOfReminder(t *testing.T) {
+	e := newEnv(t)
+	e.start(t)
+	if ok, err := e.svc.EmitDayOfReminder(t.Context(), mustDate("2026-10-14")); ok || err != nil {
+		t.Fatalf("EmitDayOfReminder with no plan = %v, %v, want false", ok, err)
+	}
+	e.reply("", fullWeek...)
+	e.mustDraft(t, false)
+	for range 2 {
+		if ok, err := e.svc.EmitDayOfReminder(t.Context(), mustDate("2026-10-14")); !ok || err != nil {
+			t.Fatalf("EmitDayOfReminder = %v, %v, want true", ok, err)
+		}
+	}
+	rows := notifytest.Rows(t, e.st, notify.DayOfReminder)
+	if len(rows) != 1 {
+		t.Fatalf("day_of_reminder rows = %+v, want one on push", rows)
+	}
+	r := rows[0]
+	if r.Key != "day_of_reminder:2026-10-14" || r.Channel != notify.ChannelPush || r.Payload.Title != "Tonight's dinner" ||
+		r.Payload.Body != "Pad Thai" || r.Payload.URL != "/dinner/"+e.ids["Pad Thai"] || r.Payload.Week != "2026-10-12" {
+		t.Errorf("day_of_reminder row = %+v", r)
+	}
+}
+
 func TestStartByIsDinnerTimeMinusMinutesForCrockPot(t *testing.T) {
 	e := newEnv(t)
 	e.start(t)