fix #385: Options dropdowns — white centered text + size-to-content popup

User gate report (Campaign OP happy-testing round, 2026-08-13): every
Config-tab dropdown drew its text gold + left-aligned and its popup a
fixed 6 rows regardless of item count. All three were unmeasured styling
divergences — the authored data (new probe menuprobe3, live DAT) says:

- button label child 0x10000355: fontColor white, hJustify=Center
- row template 0x1000035A: fontColor white, hJustify=Center
- popup ListBox 0x10000358: edge-docked L=T=R=B=1, the authored condition
  arming retail UIElement_Menu::RecalculatePopupSize @0x0046caf0 —
  popup resizes to the ListBox's summed content height, uncapped
  (0x0046e5f4..0046e66c via ResizeScrollableArea's 0x32 broadcast)

UiMenu gains three opt-in properties (ButtonTextCentered,
ItemTextCentered, PopupSizeToContent) plus retail Open @0x0046cc42's
empty-list gate; chat + vendor keep the class defaults, so their shipped
behavior is untouched. ConfigOptionsPageController.ApplyMenuChrome wires
all four corrections for the 8 Config menus with the probe citation.

The same probe found vendor's authored popup ListBox is ALSO docked while
our vendor dropdown ships G5's fixed 6-row window — filed as #386 +
register row AD-88 (UNCLEAR: the G5 retail screenshot and the decomp
mechanism conflict) instead of silently reworking a user-gated surface.

The "resolution change resizes the window" observation from the same
report is #374's designed windowed-mode behavior (display-mode switching
is #376/#377) — no change.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

docs/research/2026-08-11-campaign-op-test-script.md

@@ -9,6 +9,16 @@ Re-gate note for the previously-blank tabs: #372's viewport fix landed
 `[options] gameplay button 0x... clicked` — a silent click in that log IS
 evidence, report it per-button.
 
+**Dropdown appearance (fix #385, 2026-08-13 happy-testing round).** Every
+Config-tab dropdown (Sound Features, Resolution, texture menus, Chat Font
+Size, …) now matches the authored retail style: the button caption and the
+popup rows draw WHITE and CENTERED (not gold/left), and the popup's height
+conforms to its item count (a 3-choice menu opens 3 rows tall, a 10-mode
+Resolution list opens 10 rows tall — retail's `RecalculatePopupSize`
+size-to-content port; there is no 6-row scroll window on these menus any
+more). A clicked dropdown with NO choices no longer opens an empty popup.
+Report any dropdown still showing gold/left text or a fixed-height popup.
+
 **Caption dimming (AD-78, user-directed, gate 2).** As of this session, every
 row this script marks as a store-only row (see each section's own "Store-only
 rows" subsection, or the register row AD-78 for the complete four-controller