List the last visited workspace first in the rail

Co-Authored-By: Claude Opus 5.5 <[email protected]>

src/utils/parse-positive-id.ts

@@ -0,0 +1,20 @@
+type Params = {
+    value?: string | number | null;
+};
+
+/**
+ * A positive whole number from a cookie or query value, or null when it
+ * isn't one, so a hand-edited value never reaches a query. Surrounding
+ * whitespace is trimmed.
+ */
+export default function parsePositiveId({ value }: Params): number | null {
+    if (value === undefined || value === null) return null;
+
+    const raw = String(value).trim();
+
+    if (!/^\d+$/.test(raw)) return null;
+
+    const id = Number(raw);
+
+    return Number.isSafeInteger(id) && id > 0 ? id : null;
+}