revert: restore production to the state before 730d0bd (PM/RBAC work moved to 'pm')

Their three commits (730d0bd, 5a9b543, 387edfb) reached production by push and
auto-deployed. 387edfb expects a users.username column that the live database does
not have, so POST /api/v1/auth/login was returning HTTP 500. Their schema changes
never applied either (projects still has only id, name, description, start_date,
pm_user_id, created_at), so nothing depends on the reverted code.

This commit sets the tree back to exactly a02b3ea — verified with git diff against
it — while keeping history linear: the work itself is preserved on 'pm' at 387edfb.

frontend/src/components/RequirePmProjects.tsx

@@ -16,11 +16,11 @@ export function RequirePmProjects({ children }: { children: ReactNode }) {
   const setProjects = useAuthStore((s) => s.setProjects);
   const logout = useLogout();
 
-  const isSupervisor = user?.role === "supervisor";
-  const [state, setState] = useState<"loading" | "ok" | "empty">(isSupervisor ? "loading" : "ok");
+  const isPm = user?.role === "pm";
+  const [state, setState] = useState<"loading" | "ok" | "empty">(isPm ? "loading" : "ok");
 
   useEffect(() => {
-    if (!user || user.role !== "supervisor") {
+    if (!user || user.role !== "pm") {
       setState("ok");
       return;
     }