v1.1.0

Add PID control demo (P / PI / PD / PID step-response comparison).

• New pid-control/ demo: interactive Live Script (.m/.mlx), classic script, and GUI app
• Second-order plant controlled with a PID law, solved via ode45 (base MATLAB only)
• Compares four modes P / PI / PD / PID with the same Kp, Ki, Kd gains

PID制御デモ（P・PI・PD・PID のステップ応答比較）を追加。base MATLAB のみで動作。

v1.0.0

First public release of the matlab-edu-demos collection.

• spring-mass-damper: free-vibration simulators
  (classic script, interactive/static Live Scripts, and a GUI app)
• Base MATLAB only, no extra toolboxes

初回公開。ばね-マス-ダンパ系の振動シミュレータ一式を収録。