P14-03: Versioned shaft-wait saves, keep riders aboard, real-actor proof

- ElevatorService snapshot v2 carries the shaft-wide wait; v1 saves (written
  with every elevator dynamic_cost 0) migrate by deriving it on load, and any
  v2 mismatch, including all zeros, is rejected atomically. A genuine save
  from 50ceca0 is kept as tests/fixtures/p14-03/legacy_rush_v1.
- A guest aboard a cabin no longer decides, leaves or despawns until the
  elevator sets it down at a real landing; previously a rider told to leave
  vanished from a moving cabin.
- test_route_wait_choice now proves the rush detour and route loss with a
  worker who actually walks, every shared rider's arrival cell, service
  elevator and stair congestion, legacy migration and a new-PID restart.
- Register completion markers for the seven suites added this session and
  bring the P14 ledger in line with P14-02's completion.

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

tests/fixtures/p14-03/legacy_rush_v1/journal.log

@@ -0,0 +1 @@
+save_completed 2026-10-20T07:38:59

tests/fixtures/p14-03/legacy_rush_v1/manifest.json

@@ -0,0 +1,15 @@
+{
+	"absolute_minute": 1091,
+	"checksum_world": "baa5cb8d4eb3ed651934cca0bc1f26f22fd345dc9886a72ca383c3722438ffb9",
+	"content_pack_ids": [],
+	"created_at_real": "2026-10-20T07:38:59",
+	"day": 1,
+	"display_name": "p14_03_legacy_rush",
+	"enabled_filter_profile": "default",
+	"format_version": 1,
+	"game_version": "0.1.0",
+	"save_id": "p14_03_legacy_rush",
+	"seed": 1403,
+	"uncompressed_size": 197716,
+	"updated_at_real": "2026-10-20T07:38:59"
+}