fix: plot_wave plt.show() crash when called non-interactively

Add show=False parameter to plot_wave(); when called from dynamics.py,
pass show=False and set matplotlib Agg backend to avoid NonGuiException.
Also print full traceback on failure for easier debugging.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

dynamics.py

@@ -381,14 +381,20 @@ def run_case(config_path, runtime_base, input_dir="input", output_dir="output",
         # 6. 波形能量动画（可选）
         if config.get("step_plot_wave", 0):
             try:
+                import matplotlib
+                matplotlib.use("Agg")   # 非交互式后端，避免弹窗/报错
                 import plot_wave as pw
                 print("[run] 正在绘制波形与能量图…")
-                pw.plot_wave(
+                gif = pw.plot_wave(
                     str(output_dir_abs),
                     save_gif=int(config.get("plot_wave_save_gif", 0)),
                     save_mp4=int(config.get("plot_wave_save_mp4", 0)),
+                    show=False,
                 )
+                if gif:
+                    print(f"[run] 波形 GIF 已保存: {gif}")
             except Exception as e:
+                import traceback; traceback.print_exc()
                 print(f"[run] 绘制波形图失败: {e}")