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/index.html

@@ -129,6 +129,67 @@
       <input type="number" id="p-max-matches" value="25" min="1" max="200">
     </div>
 
+    <details>
+      <summary>Modalità Halcon</summary>
+      <div class="halcon-grid">
+        <label class="hc-row" title="16-bin orientation polarity-aware (mod 2π)">
+          <input type="checkbox" id="hc-use-polarity">
+          <span>Polarity 16-bin (F)</span>
+        </label>
+        <label class="hc-row" title="Score continuo cos(θ_t-θ_s) invece di bin">
+          <input type="checkbox" id="hc-soft-score">
+          <span>Soft-margin score (Y)</span>
+        </label>
+        <label class="hc-row" title="Sub-pixel refinement gradient field LM">
+          <input type="checkbox" id="hc-subpixel-lm">
+          <span>Sub-pixel LM 0.05 px (Z)</span>
+        </label>
+        <label class="hc-row" title="Refine congiunto Nelder-Mead (cx,cy,θ)">
+          <input type="checkbox" id="hc-refine-joint">
+          <span>Refine pose joint</span>
+        </label>
+        <label class="hc-row" title="Pyramid candidates propagation">
+          <input type="checkbox" id="hc-pyr-propagate">
+          <span>Pyramid propagate</span>
+        </label>
+        <label class="hc-row" title="OpenCL GPU offload (silent fallback CPU)">
+          <input type="checkbox" id="hc-use-gpu">
+          <span>GPU OpenCL (R)</span>
+        </label>
+
+        <div class="hc-row hc-num">
+          <label>Min recall (M)</label>
+          <input type="number" id="hc-min-recall" value="0.0" min="0" max="1" step="0.05">
+        </div>
+        <div class="hc-row hc-num">
+          <label>NMS IoU thr (A)</label>
+          <input type="number" id="hc-nms-iou" value="0.3" min="0" max="1" step="0.05">
+        </div>
+        <div class="hc-row hc-num">
+          <label>Greediness</label>
+          <input type="number" id="hc-greediness" value="0.0" min="0" max="1" step="0.1">
+        </div>
+        <div class="hc-row hc-num">
+          <label>Coarse stride</label>
+          <input type="number" id="hc-coarse-stride" value="1" min="1" max="4" step="1">
+        </div>
+        <div class="hc-row hc-num" style="grid-column:1/-1">
+          <label title="Limita area di ricerca scena: x,y,w,h (vuoto = tutta scena)">
+            Search ROI (x,y,w,h)
+          </label>
+          <input type="text" id="hc-search-roi" placeholder="es. 100,50,800,400">
+        </div>
+
+        <div class="hc-row" style="grid-column:1/-1; border-top:1px solid #444; padding-top:8px">
+          <label>Ricetta pre-trained (V)</label>
+          <div style="display:flex; gap:6px; margin-top:4px">
+            <input type="text" id="hc-recipe-name" placeholder="nome_ricetta" style="flex:1">
+            <button class="btn" id="btn-save-recipe" type="button">💾 Salva</button>
+          </div>
+        </div>
+      </div>
+    </details>
+
     <details>
       <summary>Avanzate</summary>
       <div id="adv-form"></div>