feat(web): wiring UI per modalita Halcon (M, Y, Z, V, X, R + altri)

UI espone tutti i nuovi flag tramite sezione pieghevole "Modalita Halcon"
nel pannello impostazioni. Default off = comportamento backward compat.

Flag esposti (checkbox + numerici):
- use_polarity (F): 16-bin orientation mod 2pi
- use_gpu (R): OpenCL UMat con silent fallback CPU
- use_soft_score (Y): score continuo cos(theta_t-theta_s)
- subpixel_lm (Z): refinement 0.05 px gradient field
- refine_pose_joint: Nelder-Mead 3D (cx,cy,theta)
- pyramid_propagate: top-K propagation a full-res
- min_recall (M): filtro feature-recall
- nms_iou_threshold (A): IoU bbox poligonale
- greediness: early-exit kernel
- coarse_stride: sub-sampling top-level
- search_roi: x,y,w,h area di ricerca

Persistenza ricette (V):
- Endpoint POST /recipes: training + save .npz in recipes/
- Endpoint GET /recipes: lista
- UI: campo nome + bottone "Salva" sotto i flag

Server SimpleMatchParams esteso con tutti i campi; pipeline match_simple
propaga init-flags al cache key (use_polarity/use_gpu = retrain) e
find-flags al m.find().

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

pm2d/web/static/style.css

@@ -156,3 +156,20 @@ footer h2 {
 }
 
 #col-model, #col-scene { min-width: 0; }
+
+/* Halcon-mode panel */
+.halcon-grid {
+  display: grid;
+  grid-template-columns: 1fr 1fr;
+  gap: 6px 12px;
+  margin-top: 6px;
+  font-size: 12px;
+}
+.hc-row {
+  display: flex; align-items: center; gap: 6px;
+}
+.hc-row.hc-num {
+  flex-direction: column; align-items: flex-start;
+}
+.hc-row.hc-num label { font-size: 11px; color: #aaa; }
+.hc-row.hc-num input { width: 100%; }