fix(CT-GF1): review fix round — literal DrawHere clip shape, empty-clip cull, popup input routing

Applies all 11 items from the Opus dual-lens review of 989f6652 (0
blockers, 7 SHOULD-FIX, 4 NOTE):

- S2: UiElement.DrawSelfAndChildren now pushes the ambient clip right
  after PushAlpha and wraps OnDraw + the children walk +
  OnDrawAfterChildren in ONE block — the literal UIRegion::DrawHere
  @0x0069FA30 shape, which clips an element's OWN DrawSelf too, not
  just its children (UIElement_Text::DrawSelf @0x00467AA0 locks glyph
  blits to its own clipped surface rect; UIRegion::DrawSelf
  @0x0069F1A0 blits per clip rect). Deleted the two now-redundant
  ad-hoc self-clips this supersedes: UiText.DrawText and
  UiField.DrawMultiLine both pushed their own (0,0,Width,Height) —
  exactly what the new ambient clip already provides one level up.
  Kept UiButton.DrawBlockLabel's clip: it clips to LabelBox/ValueBox,
  an authored INNER sub-rect that can be smaller than and offset from
  the button's own full rect — a genuine narrower viewport, not a
  redundant duplicate.
- S3: deleted UiItemList's `ClipsChildren => CellWidth > 0f` override
  — correct under the old opt-in-false default, inverted under the
  new default-true (an unconfigured list would stop clipping instead
  of clipping like everything else).
- S4: pinned the escaped-popup input path end to end. New
  UiAncestorClipTests test mounts a menu inside a short window on a
  real UiRoot, opens it, and proves a click in the escaped popup
  region reaches the menu through UiRoot.PopupHit (a plain top-down
  walk is proven to reject the same point first). UiRoot.WantsMouse
  now also checks PopupHit — it previously only checked Captured/
  HitTestTopDown, so a game action could fire underneath an open
  dropdown's escaped region. OnMouseDown/OnScroll already routed
  through PopupHit first (#374); unchanged.
- S5: strengthened the Titles-divider regression test's positive
  half. The old assertion only checked SOME quad's Y fell in a band —
  vacuously true given other same-band content. Now asserts the
  divider's exact rect (X and Y), then diffs against the same rect
  with the divider hidden (Visible=false) to prove the quad was
  actually attributable to it.
- S1: added UiWindowDrawCaptureSweepTests — Character/Chat/Vendor/
  Options mounted through their real production Bind entry points
  with a non-zero sprite resolver, drawn via RecordingGpuDevice,
  asserting a per-window vertex floor (~40-45% of this session's
  observed baseline: Character 588, Chat 162, Vendor 54, Options 240)
  plus one key sprite id read LIVE off the bound controller/element
  (never hardcoded). Character's key sprite (RetailChromeSprites.
  TopEdge) specifically exercises OnDrawAfterChildren, the exact path
  S2's caution note flagged. Inventory/Paperdoll/social/map-house
  skipped — no single fixture-driven top-level Bind entry point.
- S6: added the CT-GF1 subsection to the campaign plan's ledger
  (989f6652 + this fix round; CT7 re-gate still owed).
- S7: UiRenderContext.PushClipUnbounded now resets to the CANVAS rect
  (0,0,ScreenSize), not null — retail's own popup region is
  SCREEN-clipped (UIElement_Menu::MakePopup spawns a top-level region
  bounded by the screen), not truly unbounded. AD-113 amended.
- N1: UiRoot overrides ClipsChildren => false — the root's own region
  IS the screen (the viewport already scissors it), so this is a
  safety net against a momentarily zero-sized root silently blanking
  the whole UI tree under the new ancestor-clip default.
- N2: added the empty-clip subtree cull (retail's var_24 gate
  @0x0069FB8E) to DrawSelfAndChildren only — DrawOverlays is a wholly
  separate traversal untouched by this change. New test proves a menu
  inside a fully-clipped (zero-width) window still draws its open
  popup via the overlay pass while the main pass draws nothing.
- N3: CT7 script §5 now names the collapsed-toolbar check and the
  four highest-overflow windows (combat/vitals bar, Options
  bottom-button row, map/house page, floaty chat) as explicit
  eyeball items for the re-gate.
- N4: verification below covers both the working tree and the clean
  committed tree.

Decomp anchors: UIRegion::DrawHere @0x0069FA30 (var_24 gate
@0x0069FB8E); UIElement_Text::DrawSelf @0x00467AA0 (self-clip);
UIRegion::DrawSelf @0x0069F1A0; UIElement_Menu::MakePopup (screen-
clipped popup region).

Verification (both runs green, --filter "Lane!=InstalledDat&
Lane!=PreparedPackage&Lane!=Live&Lane!=Manual&Lane!=Timing&
Lane!=Windows&Lane!=Linux&Lane!=SystemFont&Purpose!=Diagnostic&
Status!=KnownFailure"): full Release solution build green; working
tree 14,900+ tests across every project (one LandblockPresentation
PipelineTests flake reproduced ONLY under full-solution parallel
load, passes standalone and on rerun — unrelated to this change,
streaming domain); InstalledDat lane green (ACDREAM_RUN_INSTALLED_DAT
_TESTS=1, Status!=KnownFailure, 205+34+3+172 App/Content/Bake/Core
tests). Clean committed tree (git stash push -u the uncommitted
owner probe + docs files, rerun, stash pop) reported in the session
summary.

src/AcDream.App/UI/UiRoot.cs carries an unrelated, pre-existing
uncommitted owner probe (ACDREAM_PROBE_UI_HOVER) — staged selectively
(git add -p) so only this commit's own two hunks (ClipsChildren
override, WantsMouse) landed; the probe hunk is untouched and stays
uncommitted, same as before this fix round.

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

src/AcDream.App/UI/UiButton.cs

@@ -857,16 +857,20 @@ public sealed class UiButton : UiElement, IUiGlobalTimeListener, IUiDatStateful
             text, font.MeasureWidth, font.LineHeight,
             boxX, boxY, boxWidth, boxHeight, align, leftOffset);
 
-        // A multi-line result (an authored '\n') clips to its own box — the
-        // button's normal draw has no ambient clip, and an oversized
-        // wrapped caption (e.g. the Skills credits button's own tight 28px
-        // height) should be cut off at the box edge rather than spill into
-        // whatever sits below the button, matching every other clipped
-        // Type-12 text box in this codebase (UiText.DrawText's own
-        // PushClip). Single-line captions — the overwhelming majority,
-        // and (post-R3-2) EVERY caption with no authored newline — never
-        // pay this cost; see this method's own doc for why a single line
-        // is deliberately left unclipped even when boxWidth was narrowed.
+        // A multi-line result (an authored '\n') clips to its own box — an oversized
+        // wrapped caption (e.g. the Skills credits button's own tight 28px height)
+        // should be cut off at the box edge rather than spill into whatever sits
+        // below the button. CT-GF1 fix round (S2) audit: this clip STAYS (unlike
+        // UiText.DrawText's and UiField.DrawMultiLine's now-deleted self-clips) —
+        // (boxX,boxY,boxWidth,boxHeight) is LabelBox/ValueBox, an authored INNER
+        // sub-rect that can be smaller than and offset from the button's own full
+        // (0,0,Width,Height) (see LabelBox's/ValueBox's own docs and the
+        // ValueBox-narrows-boxWidth branch above), so it is not redundant with the
+        // ambient (0,0,Width,Height) clip DrawSelfAndChildren now applies by default
+        // one level up. Single-line captions — the overwhelming majority, and
+        // (post-R3-2) EVERY caption with no authored newline — never pay this cost;
+        // see this method's own doc for why a single line is deliberately left
+        // unclipped even when boxWidth was narrowed.
         bool clip = lines.Count > 1;
         if (clip)
             ctx.PushClip(boxX, boxY, boxWidth, boxHeight);