Visual test surfaced three follow-ups:
1. Square box, not 1:2 rectangle.
WidthHeightRatio: 0.5 → 1.0. Retail's Vivid Target Indicator draws
a square; the earlier humanoid-aspect ratio looked wrong for
non-humanoids and didn't match retail screenshots.
2. Large flat objects (doors / lifestones / portals / corpses)
weren't selectable with the new tight 0.7 m pick sphere.
WorldPicker.Pick now takes an optional radiusForGuid callback so
the host can per-entity decide a larger radius. GameWindow's pick
site supplies a lambda that bumps to 2.0 m for any entity with
BF_DOOR (0x1000), BF_LIFESTONE (0x4000), BF_PORTAL (0x40000), or
BF_CORPSE (0x2000) set in ObjectDescriptionFlags. Default stays
at 0.7 m for humanoids and items.
3. New [B.7] pick-info diagnostic on each successful pick:
[B.7] pick-info guid=0x... itemType=0x... pwd=0x... color=(r,g,b)
Lets us verify e.g. whether a 'green NPC' really is server-side
flagged as Vendor (BF_VENDOR=0x200, retail-defined green) vs a
bug in our colour lookup. The pwd bit table is acclient.h:6431-
6463 — same flags retail's gmRadarUI::GetBlipColor branches on.
Note: textured retail-sprite corner triangles remain a B.7 follow-up
deferred per the spec. MVP uses procedural fills.