Owner settings: add a real delete for Mitarbeiter (barbers)

Rename + active-toggle already existed (this session, earlier commit)
-- this adds a genuine, permanent delete alongside them, guarded by a
confirm() prompt that points to the "Aktiv" checkbox as the reversible
alternative for someone just temporarily off. Existing bookings against
a deleted resource are left as-is (no FK in this schema, matching its
existing convention) -- the owner agenda already falls back to the raw
resource_id for a booking whose resource no longer resolves, same as
it does today for a deactivated one.

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

backoffice/app/tests/test_booking_db.py

@@ -1,5 +1,5 @@
 import threading
-from datetime import datetime, timedelta, timezone
+from datetime import datetime, time, timedelta, timezone
 
 import pytest
 
@@ -32,6 +32,30 @@ def test_get_resource_is_tenant_scoped():
     assert bdb.get_resource(CLIENT_B, r["resource_id"]) is None
 
 
+def test_delete_resource_removes_it_and_its_hours():
+    r = bdb.create_resource(CLIENT_A, _loc(CLIENT_A), "Chair 1")
+    bdb.set_resource_hours(CLIENT_A, r["resource_id"], 0, time(9, 0), time(17, 0))
+    assert bdb.delete_resource(CLIENT_A, r["resource_id"]) == r["resource_id"]
+    assert bdb.get_resource(CLIENT_A, r["resource_id"]) is None
+    assert bdb.get_resource_hours(CLIENT_A, r["resource_id"]) == {}
+
+
+def test_delete_resource_is_tenant_scoped():
+    r = bdb.create_resource(CLIENT_B, _loc(CLIENT_B), "Chair 1")
+    assert bdb.delete_resource(CLIENT_A, r["resource_id"]) is None
+    assert bdb.get_resource(CLIENT_B, r["resource_id"]) is not None
+
+
+def test_delete_resource_leaves_existing_bookings_in_place():
+    r = bdb.create_resource(CLIENT_A, _loc(CLIENT_A), "Chair 1")
+    b = bdb.create_booking(CLIENT_A, r["resource_id"], "Alice", "a@x.com",
+                            "Haircut", _dt(10), _dt(11))
+    bdb.delete_resource(CLIENT_A, r["resource_id"])
+    still_there = bdb.get_booking(CLIENT_A, b["booking_id"])
+    assert still_there is not None
+    assert still_there["resource_id"] == r["resource_id"]
+
+
 def test_create_and_get_service():
     s = bdb.create_service(CLIENT_A, "Haircut", 30, price=25)
     assert s["duration_minutes"] == 30