Add interpretive assessment layer to session reports. Every metric section
now shows color-coded severity badges (green/amber/red) computed from
configurable thresholds, replacing raw numbers with instant signal.
Includes centralized reportAssessments utility, model mismatch detection,
switch pattern recognition, and 44 new tests.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
