Add the Supply run API, item toggles and the Push to Calendar hook

GET /api/v1/shopping/{weekStart} reads the week's Supply run with its
week label, counts and groups by plan day; POST
/api/v1/shopping/{weekStart}/generate makes or remakes it through
shopping.Generate; PATCH /api/v1/shopping/items/{id} sets an item's
needed flag and answers with the list's new counts, 409 archived once
the list is in the Supply archive and 404 for an unknown item.

A successful Push to Calendar now makes the pushed week's Supply run.
Generation runs after the push is recorded and never fails or undoes
it: the 200 answer reports supply_run generated, archived or failed,
and a failure is logged as an error.

Maestro task d076480c-6c59-4c57-9023-6941badb4520.

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

internal/server/plans_test.go

@@ -23,6 +23,7 @@ import (
 	"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/plan"
+	"code.cubecraftlabs.com/Maniacs_Mansion/Meal-Quest/internal/shopping"
 	"code.cubecraftlabs.com/Maniacs_Mansion/Meal-Quest/internal/store"
 )
 
@@ -79,8 +80,12 @@ func newPlansRouter(t *testing.T) plansEnv {
 	if err != nil {
 		t.Fatal(err)
 	}
+	shop, err := shopping.NewService(st)
+	if err != nil {
+		t.Fatal(err)
+	}
 	h, err := NewRouter(logger, "dev", nil, stubAuth{}, stubSessions{}, newTestSettings(t), newTestSearch(t), newTestAI(t),
-		newTestDinners(t), newTestSuggest(t), svc, googleSvc, runner, newTestPhotos(t), fstest.MapFS{"index.html": {Data: []byte(fixtureIndex)}})
+		newTestDinners(t), newTestSuggest(t), svc, shop, googleSvc, runner, newTestPhotos(t), fstest.MapFS{"index.html": {Data: []byte(fixtureIndex)}})
 	if err != nil {
 		t.Fatal(err)
 	}