v0.4.9 — X,Y coordinates, no-switching can still clear the mainline, Q3 corrected, a clearance bug, three sounds, and the box art

A playtest review of seed 58228926 (day 6), plus one long-standing display complaint and the
first real audio beyond a placeholder.

- Coordinate labels read X,Y everywhere shown to a player, not the internal Y,X storage order.
  Display-only.
- "No switching" now means may not add or drop cars, not "never touch it" — these trains can
  still be moved onto Secondary Track to clear the mainline.
- Q3 corrected: Expedite governs WHERE a train may be left standing, not WHEN it leaves. The
  forced same-Stage departure is gone; a new fault costs 1 Revenue if an expedited train is left
  off the station when a Mainline Phase begins. Resolves "3/4 Express prints a rule it can never
  use" as a side effect.
- evaluateClearance now checks every occupant on a Mainline card before offering a judgment
  call, instead of returning on whichever it found first — found while explaining a playtest
  report, fixed with a regression test.
- Three new synthesised sounds: arrive, depart, crash.
- The splash page shows the box art.

Full detail, measurements and reasoning in CHANGELOG.md.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01FvU99NEakShRMg3nN3fHAZ

scripts/build-web.ts

@@ -10,7 +10,7 @@
  */
 
 import { execFileSync } from 'node:child_process';
-import { existsSync, mkdirSync, readFileSync, readdirSync, rmSync, writeFileSync } from 'node:fs';
+import { copyFileSync, existsSync, mkdirSync, readFileSync, readdirSync, rmSync, writeFileSync } from 'node:fs';
 import { dirname, join } from 'node:path';
 import { fileURLToPath } from 'node:url';
 
@@ -151,6 +151,17 @@ if (existsSync(replaySrc)) {
 }
 writeFileSync(join(replayOut, 'manifest.json'), JSON.stringify(manifest, null, 1));
 
+/**
+ * Static images — the splash artwork and whatever joins it. Copied verbatim, unlike the replays
+ * above: an image needs no validation, only a place in `dist/` to be served from.
+ */
+const imageSrc = join(root, 'public/images');
+if (existsSync(imageSrc)) {
+  const imageOut = join(dist, 'images');
+  mkdirSync(imageOut, { recursive: true });
+  for (const f of readdirSync(imageSrc)) copyFileSync(join(imageSrc, f), join(imageOut, f));
+}
+
 // A tiny note for whoever unzips this later and wonders what it needs.
 writeFileSync(
   join(dist, 'README.txt'),