Move PID matplotlib demo harnesses out of production modules

temp_controller.py, temp_controller_smith.py, and kalman.py imported
matplotlib at module level just to support eyeballed-plot __main__
blocks, coupling the live server's import graph to a GUI plotting lib
it never uses at runtime. Relocate those demos (and kalman_eval.py) to
scripts/demos/pid/ and strip the now-unused imports/__main__ blocks
from the production files.

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

components/pid/kalman.py

@@ -1,6 +1,5 @@
 import numpy as np
 from numpy.linalg import inv
-from matplotlib.pyplot import plot, figure, subplot, grid, show
 
 
 class Kalman:
@@ -76,57 +75,3 @@ class Kalman:
 		I = np.eye(self.N)
 		self.P = (I - K * self.H) * P
 		return self.X
-
-
-# Main
-if __name__ == '__main__':
-	dt = 1.0
-
-	params = {
-		'var_P'	: 1,
-		'var_Q'	: 0.0001,
-		'var_R'	: 0.5
-	}
-	k = Kalman(dt, params)
-
-	_x1 = np.empty(0)
-	_y1 = np.empty(0)
-	_x2 = np.empty(0)
-	_y2 = np.empty(0)
-
-	N = int(1000/dt)
-	seqn = range(0, N)
-
-	_seqn = range(0, 2*N)
-	X = np.array([dt, 0])
-	for n in seqn:
-		Z = k.process_measurement(X, 0.5)
-		# Kalman.print("Z:", Z)
-		Xp = k.process(Z)
-
-		_x1 = np.append(_x1, Z[0])
-		_x2 = np.append(_x2, Z[1])
-		_y1 = np.append(_y1, Xp[0])
-		_y2 = np.append(_y2, Xp[1])
-
-	for n in seqn:
-		X[0] = X[0] + dt
-		Z = k.process_measurement(X, 0.5)
-		# Kalman.print("Z:", Z)
-		Xp = k.process(Z)
-
-		_x1 = np.append(_x1, Z[0])
-		_x2 = np.append(_x2, Z[1])
-		_y1 = np.append(_y1, Xp[0])
-		_y2 = np.append(_y2, Xp[1])
-
-	figure(1)
-	subplot(2, 1, 1)
-	plot(_seqn, _x1, 'bx', _seqn, _y1, '-r', linewidth=1)
-	grid(True)
-	subplot(2, 1, 2)
-	plot(_seqn, _x2, 'bx', _seqn, _y2, '-r', linewidth=1)
-	grid(True)
-	show()
-
-	print("End of program")