Ask for a residence permit only where one is needed

Employees from outside the EU, the EEA and Switzerland need a residence
permit, and HR needs to know when it expires — about eighty people in
the current data, across Türkei, Serbien and Bosnien. Two columns, the
same shape as the dismissal protection: a flag and a date that only
means anything with it. The date is optional, because an open-ended
permit has none and a mandatory field would force an invented one.

The nationality coupling deliberately stays out of the database. Putting
it there would mean keeping the country list in two places — SQL and
lib/countries.ts, where the picker needs it anyway — so an EU accession
would become a migration instead of a line in a list. Worse, correcting
somebody's nationality would fail the constraint while the old permit
was still attached, which is exactly the moment someone is fixing a
mistake. The UI decides whether the fields appear, and clears them when
the nationality moves into the free-movement area.

So the list is the load-bearing part, and it is tested: 31 entries, all
of them values the picker can actually produce, no duplicates, no third
countries. A missing nationality reads as "no permit required" — an
unanswered question is a reason to record it, not to demand papers.

The permit shows on the Stammdaten tab only for the nationalities it
applies to. A line reading "Aufenthaltstitel: Nein" under an Austrian
citizenship would look like information rather than a question that does
not arise.

Filter by it and by when it expires — the question behind that being
"whose permit runs out next quarter" — plus columns in the export.

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

tests/components/TerminatePanel.test.tsx

@@ -28,6 +28,8 @@ function mitarbeiter(teil: Partial<EmployeeRow> = {}): EmployeeRow {
     birth_date: "1990-04-01",
     sv_nummer: null,
     nationality: "Österreich",
+    hat_aufenthaltstitel: false,
+    aufenthaltstitel_bis: null,
     address: null,
     address_country: null,
     postal_code: null,