feat(ux)+fix(rings): release counter #N in the wordmark; all shared-frame rings 4->8 (#11)

Roll-forward of today-slices 6fd1d9c onto the slice-8 base, two-loop hunk dropped.

Release counter (per-build GUID read as noise; +1 per commit from git rev-list,
baseline 241 -> #13, generated by GenerateBuildStamp; GUID demotes to startup.log).
Tests pinned to Label/#N >= 13; wordmark display test asserts the Label.

Flash fix (take 14 finding): consumer holds must never outlive depth x source
period — 4 slots at high refresh lap ~27ms vs a <=50ms compositor read, so a
recycled slot flashed its new frame over the lagged old one. All shared rings 4->8
(OBS/overlay precedent for ring discipline).

Camera producer now rotates an 8-deep ring + Epoch instead of a fresh ~3.7MB
array per device frame (110-220MB/s LOH churn); WebView2 capture reuses a canvas
scratch + 8-deep output ring + a reused WriteableBitmap instead of two fresh
arrays + a fresh bitmap per 10Hz tick. Paste cache stays identity-keyed (Epoch).

Services/ScreenCaptureFrameSource.cs

@@ -36,7 +36,10 @@ public sealed class ScreenCaptureFrameSource : IScreenCaptureSource
     // itself was fast. A 4-deep ring rotated round-robin is never lapped by a
     // ≤17ms consumer at 60Hz; each hand-out carries an Epoch so identity-keyed
     // consumers (the compositor's paste cache) cannot false-hit a recycled array.
-    private readonly byte[]?[] _frameRing = new byte[4][];
+    // Depth 8 (take-14 rule): depth × source period must exceed the worst consumer
+    // hold — 4 slots at 144Hz laps in ~27ms while a compositor read + lagged UI
+    // preview copy can hold a frame ~50ms; the flash was half a new frame over old.
+    private readonly byte[]?[] _frameRing = new byte[8][];
     private int _ringNext;
     private long _epoch;
     private byte[]? _row0;