feat: garden calendar + lists integrations (task 74)

- calendar-bridge.ts and lists-bridge.ts isolate cross-module deps
- scheduleOnCalendar action: creates event from care schedule with 30-min
  slot, title convention (Water/Fertilize/Repot/Prune/custom), reminder opt
- pushOverdueToTaskList action: inserts one task per overdue (plant+schedule)
  pair into the default task list, skips duplicate text entries
- CareScheduleEditor: per-row calendar 📅 button opens inline form with
  calendar select + optional reminder minutes + success link to /calendar
- Garden page header: PushOverdueButton with auto-dismissing feedback toast

src/app/garden/page.tsx

@@ -2,6 +2,7 @@ import Link from "next/link";
 import { listContainers, listPlants } from "@/modules/garden/server/queries";
 import { ContainerList } from "@/modules/garden/components/container-list";
 import { PlantList } from "@/modules/garden/components/plant-list";
+import { PushOverdueButton } from "@/modules/garden/components/push-overdue-button";
 
 type Props = {
   searchParams: Promise<{ tab?: string }>;
@@ -18,7 +19,10 @@ export default async function GardenPage({ searchParams }: Props) {
 
   return (
     <div className="page-content">
-      <h1 className="page-title">Garden</h1>
+      <div className="flex items-center justify-between mb-1">
+        <h1 className="page-title mb-0">Garden</h1>
+        <PushOverdueButton />
+      </div>
 
       <div className="flex gap-6 border-b border-[var(--ink-faint)] mb-6">
         <Link