Profile a peptide sequence: biophysical properties plus peptide-specific analyses including cell-penetrating peptide (CPP) score, antimicrobial peptide (AMP) prediction, proteolytic stability (trypsin/chymotrypsin/pepsin cleavage sites), and N-end rule half-life.

Parameters:
  sequence: Peptide amino acid sequence (typically 5-50 residues).

Returns: {properties, cpp_score, amp_score, protease_sites, half_life}