Root cause (evidence: gfx-log) of the opening-CG grey background: a CG drawn with
(alpha=0, color=white) means 'no tint' = fully opaque, but slice-A conflated the
color alpha with object opacity -> the CG rendered transparent. RenderObject now
carries TintStrength separately from Alpha (opacity); resolution keeps textured
objects opaque. Tests updated to the evidence-based semantics.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
0x202/0x203 now route through GfxState.SetObjectColor (sets HasColor);
SnapshotVisibleObjects resolves Alpha/Tint/BlendKind. Drops the stale
'alpha deferred' trace stub — alpha/tint is now consumed by the compositor.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
