feat: garden containers crud (task 71)

- add listContainers/getContainer/searchContainers queries
- add createContainer/updateContainer/deleteContainer server actions with logActivity
- add ContainerList, ContainerDetail, ContainerForm client components
- add /garden, /garden/containers/[id], /garden/containers/new pages
- register garden.container entity with share + search in manifest
- add sprout icon to NavIcon registry
- add garden e2e test spec

src/components/nav-icon.tsx

@@ -1,6 +1,7 @@
 import {
   Bell,
   Calendar,
+  Sprout,
   CalendarDays,
   CheckSquare,
   ChevronDown,
@@ -68,6 +69,7 @@ const ICONS: Record<string, React.ComponentType<LucideProps>> = {
   phone: Phone,
   filter: Filter,
   sun: Sun,
+  sprout: Sprout,
   mail: Mail,
   menu: Menu,
   more: MoreHorizontal,