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>

CMakeLists.txt

@@ -52,6 +52,7 @@ add_library(sacred_re SHARED
     src/mods/chainlightning.cpp
     src/mods/escape.cpp
     src/mods/recordcache.cpp
+    src/mods/megamap.cpp
 )
 target_include_directories(sacred_re PRIVATE src)
 target_compile_options(sacred_re PRIVATE ${SACRED_RE_CXX_FLAGS})