Measurement, optimal filtering (1/3): problem statement and preliminary example code

New channel Modeling, Identification, Control (A. Sala): title sample judged 'whole' (A university professor's structured teaching series on control theory, modeling, and estimation with worked examples and); passed a second screen for sellers/exam-prep/re-uploads; 3 of 3 sampled transcripts showed teaching, 0 not; every title checked strictly; oEmbed verified.