CLAUDE: CUAS cleanup — remove pre-DNN/dead paths; LReLU -> linear

Layer-1 is DNN-only; predecessor code preserved at git tag cuas-layer1.
Removed: 3d3 coarse-velocity path (curt_3d3_*, rleak1, convolve3D3LReLU);
C5P matched-filter / Bayes-posterior / whitening (curt_c5_matched/en/post/.../white*/from_pix);
LReLU rectification (curt_rleak0/pyr -> linear alpha=1, LoG kept);
distribution-vote (-GVOTE/-GHEADS, voteScatterGrid); curt_dnn_t8frac.
28 dialog params dropped; dialogQuestions/dialogAnswers re-verified aligned (44 widgets = 44 getNext). ~1841 lines removed.
Deprecated (kept): curt_stage2_model, MF-S S convention.
Kept: DNN front-end, recurrent, synth-test, SUBAVG, pyramid, LoG (linear). Build OK.

Runtime-untested (dialog) — verify a run; restore point: tag cuas-layer1.
Co-authored-by: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

src/main/java/com/elphel/imagej/cuas/rt/CuasDnnInfer.java

@@ -161,7 +161,8 @@ public class CuasDnnInfer implements AutoCloseable {
      *  Vx/Vy already bounded by the model, sigma=exp(logvar/2).
      *  MF-S models (option a, Andrey 2026-06-18): channel 0 is the RAW matched-filter path-sum S
      *  (clamp>=0), NOT a det logit -> read raw, no sigmoid (sigmoid would re-saturate the unbounded
-     *  response). S is then the informative vote weight directly (CuasDetectRT.voteScatter). By Claude on 06/18/2026 */
+     *  response). S is then the informative vote weight directly (CuasDetectRT.voteScatter). By Claude on 06/18/2026
+     *  DEPRECATED 2026-06-20 — may be revisited for Layer 2 // By Claude */
     public double[][] inferROIReg(float[][] frames, int width, int height, Rectangle roi) throws Exception {
         final int N = frames.length;
         final int P = patch, half = P / 2;