Builder, upcoming page, mods page for the current mods

- builder.html: build C900NXS.UPD in the browser (official 1.31 update in,
  mods ticked with their dependencies, no-liability and Claude Code
  confirmations, download). Ports of upd.py, the LZSS packer and the mods'
  application; the result is checked against the SHA-256 the Python
  patcher gives and is byte for byte the patcher's file.
- builder/data.js from tools/make_builder_data.py: the mods' bytes per
  combination; firmware parts (UTILITY table, HOT KEYS box, the asset
  blob's resource table) are made from the user's own update.
- index.html: rgb_waveform, extended_bpm, phasemeter, cuecolours,
  hotcuekeys (experimental), ledsaver, credit; stable/experimental and a
  green "ran on a player" dot.
- upcoming.html: beat jump, stems, uniform Camelot / Open Key, 3-band
  waveform.
- docs.html: the builder, the new mod names, hot cue loading and locks.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

style.css

@@ -287,3 +287,92 @@ footer .ai .dot { width: 8px; height: 8px; border-radius: 50%; background: var(-
   .keys .b { font-size: 1.1rem; }
   .diff li { grid-template-columns: 1fr; gap: 0; }
 }
+
+/* ---- status: stable / experimental / planned / feasibility, and the "ran on a player" dot ---- */
+.state {
+  font: 700 .66rem/1 var(--mono); letter-spacing: .08em; text-transform: uppercase;
+  padding: 6px 8px; border-radius: 7px; border: 1px solid currentColor; white-space: nowrap; align-self: flex-start;
+}
+.state.stable { color: var(--ok); }
+.state.experimental { color: var(--warn); }
+.state.planned { color: var(--accent-2); }
+.state.feasibility { color: #b48cff; }
+.player {
+  display: inline-flex; align-items: center; gap: 6px; font-size: .78rem; color: var(--muted); white-space: nowrap;
+}
+.player::before {
+  content: ""; width: 9px; height: 9px; border-radius: 50%; background: var(--ok);
+  box-shadow: 0 0 0 3px color-mix(in srgb, var(--ok) 22%, transparent);
+}
+.player.no::before { background: var(--faint); box-shadow: none; }
+
+/* ---- builder ---- */
+.builder { padding: 48px 0 72px; max-width: 900px; }
+.builder h1 { font-size: clamp(2rem, 4vw, 2.8rem); letter-spacing: -.03em; margin: 10px 0 10px; }
+.builder .lead { color: var(--muted); font-size: 1.05rem; margin: 0 0 18px; }
+.step { display: grid; grid-template-columns: 44px 1fr; gap: 16px; padding: 26px 0; border-top: 1px solid var(--line); }
+.step-n {
+  width: 36px; height: 36px; border-radius: 50%; display: grid; place-items: center;
+  background: var(--accent); color: #fff; font-weight: 800;
+}
+.step h2 { margin: 2px 0 6px; font-size: 1.25rem; }
+.step p { color: var(--muted); margin: 0 0 14px; }
+.drop {
+  display: flex; flex-direction: column; align-items: center; justify-content: center; gap: 6px;
+  border: 2px dashed var(--line); border-radius: 14px; padding: 26px; cursor: pointer; text-align: center;
+  background: var(--card); transition: border-color .15s ease;
+}
+.drop:hover, .drop.over { border-color: var(--accent-2); }
+.drop.has { border-style: solid; border-color: var(--ok); }
+.drop input { position: absolute; width: 1px; height: 1px; opacity: 0; }
+.drop-s { color: var(--faint); font-size: .88rem; }
+.picks { display: grid; gap: 10px; }
+.pick {
+  display: grid; grid-template-columns: 22px 1fr auto; gap: 12px; align-items: start;
+  background: var(--card); border: 1px solid var(--line); border-radius: 12px; padding: 14px; cursor: pointer;
+}
+.pick.on { border-color: color-mix(in srgb, var(--accent) 55%, var(--line)); }
+.pick input { margin-top: 4px; width: 17px; height: 17px; accent-color: var(--accent); }
+.pick-main { display: flex; flex-direction: column; gap: 3px; }
+.pick-name { font-weight: 700; }
+.pick-name code { font-size: .78rem; color: var(--muted); margin-left: 4px; }
+.pick-what { color: var(--muted); font-size: .93rem; }
+.pick-by { color: var(--faint); font-size: .82rem; }
+.hint { color: var(--faint); font-size: .88rem; margin-left: 10px; }
+p.hint { margin: 10px 0 0; }
+.agree { display: flex; gap: 10px; align-items: flex-start; margin: 10px 0; color: var(--muted); cursor: pointer; }
+.agree input { margin-top: 5px; width: 17px; height: 17px; accent-color: var(--accent); flex: none; }
+.agree strong { color: var(--text); }
+.btn[disabled] { opacity: .45; cursor: not-allowed; filter: none; }
+button.btn { font: inherit; font-weight: 700; cursor: pointer; }
+.log {
+  margin-top: 16px; background: #07090d; border: 1px solid var(--line); border-radius: 12px; padding: 12px 14px;
+  font: 13px/1.7 var(--mono); color: #c9d1de; max-height: 260px; overflow: auto;
+}
+.log .ok { color: var(--ok); }
+.log .bad { color: var(--bad); }
+.result { margin-top: 18px; display: grid; gap: 12px; }
+.result .btn { justify-self: start; }
+.result .sum { color: var(--muted); font-size: .85rem; word-break: break-all; }
+.result details { color: var(--muted); }
+.result summary { cursor: pointer; color: var(--text); font-weight: 600; }
+
+/* ---- upcoming ---- */
+.upcoming { padding: 48px 0 72px; }
+.upcoming h1 { font-size: clamp(2rem, 4vw, 2.8rem); letter-spacing: -.03em; margin: 10px 0 10px; }
+.upcoming .lead { color: var(--muted); font-size: 1.05rem; margin: 0 0 28px; max-width: 760px; }
+.card .meta { display: flex; flex-wrap: wrap; gap: 8px; align-items: center; margin-left: auto; justify-content: flex-end; }
+@media (max-width: 560px) {
+  .step { grid-template-columns: 1fr; gap: 8px; }
+  .pick { grid-template-columns: 22px 1fr; }
+  .pick .state { grid-column: 2; justify-self: start; }
+  .card .meta { margin-left: 0; justify-content: flex-start; width: 100%; }
+}
+@media (max-width: 560px) {
+  .tabs { gap: 2px; padding: 3px; }
+  .tabs a { padding: 6px 8px; font-size: .8rem; }
+  .theme-btn { width: 32px; height: 32px; flex: none; }
+}
+@media (max-width: 360px) {
+  .tabs a { padding: 5px 6px; font-size: .74rem; }
+}