Render the keystroke badge and step caption as a solid yellow rectangle
with no border glyphs and a one-cell text margin, instead of a
rounded-border box — deliberately unlike the app's bordered panels so
the demo overlays read as a distinct, eye-catching callout. Shared
fill_overlay_rect helper (borderless Block fill + inset Paragraph).
Snapshots regenerated; ADR-0047 D4 wording updated.
Add `--demo` (and the RDBMS_PLAYGROUND_DEMO env fallback) to enter
demonstration mode, threaded onto App.demo_mode through run_loop —
mirrors the --no-undo plumbing. Off by default, zero footprint when
off. The --help line advertises only the visible keystroke badges;
the Ctrl+] caption trigger is kept low-profile (ADR-0047 D6 updated).
Phase A of ADR-0047; behaviour (badges/captions) lands in B and C.
Accepted decision record for the in-app demo overlay: a --demo mode
that shows automatic keystroke badges ([TAB], [ENTER], …) and a
stealth Ctrl+]-delimited step-caption buffer, both as floating
black-on-yellow boxes at the output panel's bottom-right. All forks
user-confirmed; a /runda pass contributed 10 tightening findings.
Indexed in docs/adr/README.md.