widescreen: draw creatures across the whole view; HUD: copy the cursor per thread

- Creatures were culled beyond 1024+200 x 768+200 screen pixels (cmp 4C8h /
  3C8h in both object passes): invisible in the right part of a wide view,
  and the player too once the centre passed 1224. The bounds follow the
  render size now.
- Centre immediates written as negatives (-200h / -180h), missed before:
  the row renderer's static object origin (0x62babb) and aiming at the
  cursor (0x4fb620).
- HUD: moved windows no longer shift the shared mouse cursor object; the
  cursor accessor (0x6550f0) hands them a per-thread shifted copy and writes
  back what they changed. World input on other threads read the shifted
  position now and then, which made hold-to-move jerky.

Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>

docs/widescreen.md

@@ -111,6 +111,14 @@ only grows horizontally. `[widescreen] Height=0` renders natively 1:1
   an enlarged view object
 - 3D ortho extents: world (+-267 x +-200, zoomed and unzoomed) and cGranny
   (+-512 x +-384, incl. cUI_NetGranny for HUD items)
+- creature clip test in both object passes (`0x62f988`, `0x6315cb`):
+  creatures are drawn only within -200 .. 1024+200 x -200 .. 768+200 screen
+  pixels (`cmp 4C8h` / `cmp 3C8h`); unpatched, creatures in the right part of
+  a wide view were invisible, and above ~2450 px width (centre > 1224) even
+  the player
+- centre immediates written as negatives (`add reg, 0FFFFFE00h`,
+  `lea [..-200h]`), missed by a search for 200h: the row renderer's static
+  object origin (`0x62babb`) and aiming at the cursor (`0x4fb6ef`)
 - the inverse projection `0x623a20` (screen -> view) uses 1/1024 and 1/768:
   game logic (camera follow `0x44d9f0`) converts world -> screen -> view with
   the device's current projection; unpatched it sent the camera off-world
@@ -146,8 +154,5 @@ sector in every direction. The widened view needs at most +-1835 x +-768 px
 
 ## Open questions
 
-- Above ~2300 px render width (between 2304 and 2816) the player is not drawn
-  although monsters are (`cCreature::vf14` still called). Not hit at the
-  default size; some per-view limit of ~40 tile columns, not found yet.
 - Fixed-size per-view buffers (e.g. `+0x80e40`, 5 vectors at `+0x96ad0` with
   capacity 0x200) - do they overflow at 3440x1440 (47 columns x 54 rows)?