Door-game ANSI rendering fixed: proper CP437 decoding, better font, cleaner fit

[UPDATE] The BBS door-game terminal now renders ANSI art correctly.

Why it was bad: incoming bytes from the door-game server (GameSrv / BBSLink) were decoded as UTF-8. Classic BBS doors emit raw CP437 bytes — box-drawing (─│╔╗═), shades (░▒▓), and full/half blocks (█▀▄▌▐) all live in the high byte range. UTF-8 decode replaced every one of them with U+FFFD, so the menus and art were garbage.

What changed in public/assets/js/door-games.js:

• Added an inline CP437 → Unicode translation table. Bytes < 0x80 pass through as ASCII (ESC sequences, command chars, digits); bytes ≥ 0x80 map to the correct Unicode glyph (box-drawing, Greek letters, math symbols, blocks).
• Replaced new TextDecoder().decode(...) with decodeCp437(arrayBuffer). Outbound text (what the player types) stays as-is — ASCII typing is identical in all three encodings.
• Font stack upgraded: ui-monospace, "Cascadia Mono", "DejaVu Sans Mono", Menlo, Consolas, "Lucida Console", monospace. These fonts have pixel-exact box-drawing glyphs so the lines connect without gaps. (Old default "Courier New" has incomplete box coverage.)
• Expanded the xterm ANSI palette to the full 16-color set (was just 4 color entries).
• convertEol: false — door games send proper CRLF already; the conversion was causing double newlines that tore ANSI screens.
• Terminal fit no longer pokes at term._core._renderService... private internals. New measureCell() drops an off-screen 80-char span into the DOM, measures its bounding rect, divides by 80 to get per-cell width — stable across xterm versions.
• Terminal focuses automatically on WebSocket open so keyboard input works immediately.

Automated system post — 2026-04-17 14:37:16 CDT