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/draft.go

@@ -10,6 +10,7 @@ import (
 
 	"code.cubecraftlabs.com/Maniacs_Mansion/Meal-Quest/internal/ai/harness"
 	"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/dinners"
 	"code.cubecraftlabs.com/Maniacs_Mansion/Meal-Quest/internal/household"
@@ -147,6 +148,12 @@ func (s *Service) request(ctx context.Context, weekStart store.LocalDate) (skill
 // draft_week was given: a day whose dinner is no longer in it, or is in it
 // as a Regular rather than the Quest log or the other way round, leaves
 // everything as it is, failing with ReasonPoolChanged.
+//
+// A stored draft emits plan_ready, keyed by the week, in the same
+// transaction, naming the drafted dinners Monday to Sunday. The key is the week's,
+// so only the AI's first draft of a week notifies: a redraft (Rebuild week)
+// stores no second notification. A manual swap never drafts, so never
+// notifies.
 func (s *Service) storeDraft(ctx context.Context, weekStart, thisWeek store.LocalDate, confirm bool, base int64, week skills.Week) (string, error) {
 	var planID string
 	err := s.st.WithTx(ctx, func(tx *sql.Tx) error {
@@ -156,8 +163,10 @@ func (s *Service) storeDraft(ctx context.Context, weekStart, thisWeek store.Loca
 			return fmt.Errorf("plan: list draft pool: %w", err)
 		}
 		pool := make(map[string]string, len(rows))
+		names := make(map[string]string, len(rows))
 		for _, d := range rows {
 			pool[d.ID] = d.Status
+			names[d.ID] = d.Name
 		}
 		for _, d := range week.Days {
 			status, ok := pool[d.DinnerID]
@@ -215,11 +224,16 @@ func (s *Service) storeDraft(ctx context.Context, weekStart, thisWeek store.Loca
 				return fmt.Errorf("plan: put %s of %s: %w", d.Date, planID, err)
 			}
 		}
-		return nil
+		planned := make([]string, len(week.Days))
+		for i, d := range week.Days {
+			planned[i] = names[d.DinnerID]
+		}
+		return s.notifier.EmitTx(ctx, tx, chat.PlanReady(weekStart, thisWeek, planned))
 	})
 	if err != nil {
 		return "", err
 	}
+	s.notifier.Wake()
 	return planID, nil
 }