Capture original WPF ImageBrush shader sampler frames

[wieslawsoltes]

Consolidated into #360. The original head db3636790552d3ed4efe175dbd9d065c5dc7d1c8 is preserved in that integration branch. This draft is closed as superseded; implementation and qualification continue in #360.

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Adds independent original Microsoft WPF ImageBrush ShaderEffect observations: 24 cases, 72 replays, 18 exact independent color controls and 5 complete-pixel equivalence pairs. Preserves the existing 25 arithmetic cases and shared deadlines. Distinguishes inert bare-visual attached properties from actual serialized visual options, including inherited Nearest and an already-rendered own-mode reset. Retains absolute/relative non-tiled full-source viewbox mapping and source DPI. Exact original reference head 5e13e58 passed workflow 37013264907 on both architectures; x64 qualifies all 24 sampler cases, ARM64 remains an explicit unsupported-software control with zero shader cases qualified. Receipt hashes and historical diagnostic failures are documented. Normally merged the parent allocation-measurement fix. Stacked on #264; full exact-head Build and all relevant checks remain required before merge. This original reference does not qualify native/source-host/package parity.

[wieslawsoltes]

Original Windows x64 evidence has exposed a real mismatch with the existing native sampler fixture assumptions: the first ImageBrush case produces a linear red/green ramp, not hard nearest stripes, despite nearest options on the effect visual and brush. The failed source artifacts are retained. Current head adds two parent-Nearest controls and captures all 16 cases/48 replays before reporting any pixel failures; it does not weaken their assertions. A failed capture writes a separately named failed receipt, reports zero qualified cases and fails CI. Existing 25 arithmetic cases passed unchanged in the first x64 run. Native filtering/render-state ordering and source-host parity remain open until this difference is resolved.

[wieslawsoltes]

Normally merged the parent shader fix and combined matrix controls; current head db36367. The translator and paired GPU fixture exactly match parent #264; original Windows reference inputs are unchanged. Replacement whole Build: https://github.com/wieslawsoltes/ProGPU/actions/runs/37022067204 . No runtime was staged from an incomplete producer.