Maps in widened views: TAB overlay in place, M map across the full width

- hud: shift SetViewport/Clear with moved windows (TAB overview map)
- megamap: view constants patched to the render width (clip, scroll limit,
  edge scrolling, centre, dark band, zoomed view and its markers); frame
  stretched to the screen edges, zoom controls and their click area centred
- hud: Anchor::Screen windows are drawn and clicked unshifted but still own
  the event scope
- autotest waits for log markers instead of fixed delays (~18 s per run)

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

docs/hud.md

@@ -86,3 +86,32 @@ tests. Visible dialog tooltips: `mods::hud::VisibleDialogTooltips`.
 
 The standalone control hooks (buttons, texts) above turned out not to be what
 the quest dialog is made of; they stay, for top-level controls in general.
+
+## Large map (M) across the render width
+
+`mods/megamap.cpp`. cUI_Megamap (vtable 0x894714) is not moved like the other
+windows (`Anchor::Screen`: drawn and clicked unshifted); its 1024x768 view is
+widened instead, when the render size is applied (`PatchLayout`):
+
+| What | Where | Game | Now |
+|---|---|---|---|
+| cursor at the right edge (edge scrolling, cursor shape) | 9 × `cmp reg, 3FFh` 0x6c7625..0x6c9e32 | 1023 | width − 1 |
+| tiles right of the view skipped; labels flipped left | `cmp reg, 400h` 0x6c9aa3, 0x6ca2c6, 0x6ca2e5 | 1024 | width |
+| largest scroll x = map width (+0xc0160, 2048) − view | `add eax, -400h` 0x6c9edd | −1024 | −width |
+| view centre (zoom frame, centred image) | 0x6ca53f, 0x6ca637, 0x6ca645 | 0x200 | width / 2 |
+| scroll centred on the hero; zoomed view; its quest markers | `[0x88e6fc]` (512.0) at 0x6c7bfe, 0x6cb27a, 0x6ccb7f, 0x6cf782 | 512 | own float |
+| zoomed view: other markers at 768 − d (centre + 256) | `[0x890040]` (768.0) at 0x6ce156 | 768 | width / 2 + 256 |
+| dark band, right outer / inner edge | vertex immediates 0x6ca774, 0x6ca808 / 0x6ca7bc, 0x6ca84c | 1024 / 954 | width / width − 70 |
+
+The frame is child statics of the window (vector at +0x78..+0x7c; measured:
+corners 41×44, 32 px tiles, left side x < 48, right side from x 976). On
+Show (vf24 0x6c7930) the right side moves to the screen edge, the top and
+bottom tiles stretch over the wider span, and the four controls the map holds
+itself (+0xc0440, +0xc04bc statics, +0xc0544, +0xc0600 buttons: the zoom
+controls, absolute positions) stay centred, and so does the rectangle around
+them at +0xc0538: the map passes only clicks inside it to the buttons
+(0x6c7f32). Each control is placed once (the
+game lays them out at creation only).
+
+A window anchored `Screen` still counts as the outermost scope for events, so
+its child buttons (hooked as standalone controls, `Center`) don't shift again.