Creatures report at the portal and set up their bed; payday wages are fetched from the treasury

- New creatures report at the portal (2 s), walk to the lair (flyers: aerie), set up their
  bed (4 s) and only then do as they like; without a reachable lair they start right away
- Payday: the training bill is paid at once; every creature goes for its wage at a random
  moment within about a minute, to the nearest treasury tile holding treasure (or the core),
  and takes it out of that tile; no gold = an angry creature; unreachable = paid anyway
- Tests for the arrival and the walking payday

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

lang/en.lang

@@ -572,3 +572,8 @@ account.users_changed = Users updated.
 standalone.running = Preparing the standalone version ...
 standalone.done = DungeonCraft.html downloaded: open it in any browser, no server needed. Your downloaded savegames load there too.
 standalone.failed = The standalone version could not be downloaded.
+job.register = Reporting at the portal
+job.make_bed = Setting up its bed
+job.fetch_wage = Fetching its wage
+msg.payday_walk = Payday! {0} creatures fetch their wages from the treasury ({1} gold incl. training).
+msg.wage_unpaid = Your {0} found no gold for its wage and is furious!