feat: implement person name utility functions and update related components for name handling

libs/ui/src/index.ts

@@ -23,3 +23,4 @@ export * from "./lib/feedback/use-error-handler";
 export * from "./lib/data/useServerTable";
 export * from "./lib/landing/LandingPage";
 export * from "./lib/landing/landing-copy";
+export * from "./lib/utils/person-name";

libs/ui/src/lib/utils/person-name.ts

@@ -0,0 +1,19 @@
+/**
+ * Splits and joins a person's name between the account's single `name.en`
+ * string and the profile's separate `firstName`/`middleName`/`lastName`
+ * fields.
+ *
+ * The account has no first/middle/last columns of its own (that model lives
+ * only on the profile), so this is the one place that heuristic lives —
+ * reused everywhere a name crosses that boundary: the signup form joins into
+ * it, the Identity Details wizard step and the Profile page's Personal tab
+ * both split out of it.
+ */
+export function splitPersonName(fullName: string) {
+  const [firstName = '', middleName = '', ...rest] = fullName.trim().split(/\s+/);
+  return { firstName, middleName, lastName: rest.join(' ') };
+}
+
+export function joinPersonName(parts: { firstName: string; middleName?: string; lastName: string }) {
+  return [parts.firstName, parts.middleName, parts.lastName].filter(Boolean).join(' ');
+}