Adds a styled-HTML dialog diagram (User vs Model bubbles, dashed amber
divider labeled "new session — context wiped", and a two-line caption
strip) to make the stateless behavior of LLMs visible. Drawn rather than
imported as PNG, mirroring slide-12's inline-diagram conventions. Old
slides 10..48 shifted to 11..49 via sentinel-replacement; banner
comments updated in the same pass to keep the deck's zero-drift state.
No new CSS classes — all layout via inline styles consistent with
surrounding slides.
Co-Authored-By: Claude <noreply@anthropic.com>