fix: cap adattivo al 50% varianti + form e finestra risultati ridimensionabili

- max_vars_full = max(max_matches*8, n_variants // 2): protegge perf con
  molte scale mantenendo metà delle varianti al full-res (vs intero senza cap
  che dava 22s su 864 varianti, vs 80s screenshot utente)
- Dialog tkinter: resizable, minsize 360x420, Entry col peso 2 espandibile
- Finestra risultati cv2: WINDOW_NORMAL con resizeWindow iniziale 1600x900

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

pm2d/gui.py

@@ -55,21 +55,29 @@ def edit_params(defaults: dict, template_bgr: np.ndarray | None = None) -> dict
     """
     root = tk.Tk()
     root.title("Parametri Pattern Matching 2D")
+    root.resizable(True, True)
+    root.minsize(360, 420)
     try:
         root.attributes("-topmost", True)
     except Exception:
         pass
 
+    # Grid root: fa espandere la cella (0, 0)
+    root.columnconfigure(0, weight=1)
+    root.rowconfigure(0, weight=1)
+
     result: dict = {}
     entries: dict[str, tk.Entry] = {}
 
     frame = ttk.Frame(root, padding=12)
     frame.grid(row=0, column=0, sticky="nsew")
+    frame.columnconfigure(0, weight=1)
+    frame.columnconfigure(1, weight=2)
     for i, (key, label, _typ) in enumerate(PARAM_SCHEMA):
         ttk.Label(frame, text=label).grid(row=i, column=0, sticky="w", padx=4, pady=3)
-        e = ttk.Entry(frame, width=14)
+        e = ttk.Entry(frame)
         e.insert(0, str(defaults.get(key, "")))
-        e.grid(row=i, column=1, padx=4, pady=3)
+        e.grid(row=i, column=1, padx=4, pady=3, sticky="ew")
         entries[key] = e
 
     hint_var = tk.StringVar(value="")
@@ -392,6 +400,9 @@ def show_results(
     else:
         composed = annotated
     disp = _fit_for_display(composed, max_side=1600)
+    cv2.namedWindow(WINDOW_RESULT, cv2.WINDOW_NORMAL)
+    cv2.resizeWindow(WINDOW_RESULT, min(disp.shape[1], 1600),
+                     min(disp.shape[0], 900))
     cv2.imshow(WINDOW_RESULT, disp)
     print("\n[r] parametri  [o] nuovo ROI  [m] nuovo modello  [s] nuova scena  [q/Esc] chiudi")
     action = "quit"