feat: migrate setup visibility from boolean to three-tier system

Replace isPublic boolean with visibility enum (private/link/public) across
the full stack. Add shares table to schema for future share link support.
Update all services, routes, schemas, hooks, components, and tests.

Plan: 32-01 (Setup Sharing System - Schema Migration)

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

src/client/hooks/useSetups.ts

@@ -11,7 +11,7 @@ import {
 interface SetupListItem {
 	id: number;
 	name: string;
-	isPublic: boolean;
+	visibility: "private" | "link" | "public";
 	createdAt: string;
 	updatedAt: string;
 	itemCount: number;
@@ -39,7 +39,7 @@ interface SetupItemWithCategory {
 interface SetupWithItems {
 	id: number;
 	name: string;
-	isPublic: boolean;
+	visibility: "private" | "link" | "public";
 	createdAt: string;
 	updatedAt: string;
 	items: SetupItemWithCategory[];
@@ -88,8 +88,10 @@ export function useCreateSetup() {
 export function useUpdateSetup(setupId: number) {
 	const queryClient = useQueryClient();
 	return useMutation({
-		mutationFn: (data: { name?: string; isPublic?: boolean }) =>
-			apiPut<SetupListItem>(`/api/setups/${setupId}`, data),
+		mutationFn: (data: {
+			name?: string;
+			visibility?: "private" | "link" | "public";
+		}) => apiPut<SetupListItem>(`/api/setups/${setupId}`, data),
 		onSuccess: () => {
 			queryClient.invalidateQueries({ queryKey: ["setups"] });
 		},