make the email url the selection instead of a mirror of it

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

src/apps/officer-web/Screens/Dashboard/Email/shared.ts

@@ -0,0 +1,12 @@
+import { useParams } from 'react-router';
+
+// Which email is open is `/email/:emailId`. The route pair already existed, but the URL was a mirror
+// rather than the state: the selection lived in an `EMAIL_SELECTED` global and two effects copied it
+// back and forth with the route. That round-trip is what kept a row a `<button>` — nothing to link to,
+// no cmd-click, no middle-click — and it meant Back raced the effect that had just written the URL
+// with `replace`. The param is the state now; there is nothing to keep in sync.
+
+export const emailPath = (id: string) => `/email/${encodeURIComponent(id)}`;
+
+/** The open email, or null on the bare `/email` route — which is a real state, not one to redirect away. */
+export const useSelectedEmailId = (): string | null => useParams<{ emailId?: string }>().emailId ?? null;