feat(admin): reorganize housekeeping and strengthen shared workflows

src/lib/admin-table-state.test.ts

@@ -0,0 +1,17 @@
+import { expect, it } from "vitest";
+import { tablePageNumbers } from "./admin-table-state";
+
+it.each([
+	[1, 1],
+	[1, 7],
+	[6, 7],
+	[7, 7],
+	[50, 100],
+	[100, 100],
+])("includes the current page %i/%i and stays in bounds", (page, last) => {
+	const pages = tablePageNumbers(page, last);
+	expect(pages).toContain(page);
+	expect(pages.length).toBeLessThanOrEqual(5);
+	expect(pages.every((p) => p >= 1 && p <= last)).toBe(true);
+	expect(new Set(pages).size).toBe(pages.length);
+});