feat: floodlit roadside billboard carries the selected-builds case studies

docs/overnight/LOG.md

@@ -39,3 +39,11 @@ Run: `npm run build:preview` then serve `dist` (dev server shows a blank page).
 - **Known weaknesses:** the free side is narrow because of the camera frame shift, so the big pass is brief; plates read mostly white under tonemapping; no lit number glyphs on the plates.
 - Screenshots: docs/overnight/round4/.
 
+## Round 5: Drive-In (Selected builds billboard)
+- **What:** a floodlit roadside billboard (22 x 15 m, right shoulder) carries the case-study media in the world: medication tracker triptych, opinion-dynamics chart pair, footy-tracker typographic plate. Floods relight per project as scroll passes each case study (reverse runs backwards), light spill on the shoulder, hover on a gallery image zooms that shot onto the board, floods breathe with the bass pulse. Reduced motion/static: CSS flood gradient on the active gallery.
+- **Why:** Selected builds hold the only real proof and had no world beat; DOM evidence and scene now share one object.
+- **Build:** scene/world/billboard.ts, journey/billboard-progress.ts + billboard-feed.ts, useBillboard.ts, billboard.css. 786 tests, initial JS 116.5 KB gz (**3.5 KB left**), scene chunk ~210 KB.
+- **Verdict: KEEP with fixes** (Fable, hardware GL): the delivered board was an 80 px speck, so it was rebuilt at 2.4x, moved to x 24, lit at chapter entry, floods widened, charts dimmed so bloom does not blow them out; narrow-viewport placement added.
+- **Known weaknesses:** the 92%-wide panel hides the board while reading (visible at chapter entry, in gaps between case studies and at exit); phone screenshots read dim; ~140 px on phones; test-only telemetry.
+- Screenshots: docs/overnight/round5/.
+