brain: plug into the page's hooks instead of overriding its functions

hooks.djPrompt, hooks.stationOpened, hooks.jobMade and hooks.reacted carry what
the djPrompt / openStation / makeJob / react reassignments did; same behaviour.
countPlay reads its one row with db.get instead of db.all().

Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01K6897PWcUEwHiqZMcVnNF6

brain.js

@@ -124,19 +124,17 @@ function tasteText() {
     (likes ? ` Words it warms to: ${likes}.` : "") + (dislikes ? ` Words it cools on: ${dislikes}.` : "") +
     ` Aim near the likely region and lean on the warm words unless the listener's own words say otherwise; keep some variety.`;
 }
-const _djPromptBase = djPrompt;                                       // assignment, not a declaration: a declaration would hoist over this
-djPrompt = function () {
-  const base = _djPromptBase();
+/* the page's hooks (index.html › hooks): the taste text rides into the DJ's prompt, and a station opening retrains */
+hooks.djPrompt = (base) => {
   const tt = tasteText();
   return tt ? base.replace("\nWrite the NEXT track.", `\n${tt}\n\nWrite the NEXT track.`) : base;
 };
-const _openStation = openStation;
-openStation = async function (seed, s) { await _openStation(seed, s); rebuildBrains().catch(() => {}); };
+hooks.stationOpened = () => { rebuildBrains().catch(() => {}); };
 
 /* ---------- plays: every start counts, and so does every pass of the loop ---------- */
 async function countPlay(spec) {
   if (!spec || !spec.id) return;
-  const row = (await db.all()).find((t) => t.id === spec.id); if (!row) return;
+  const row = await db.get(spec.id); if (!row) return;
   row.plays = (row.plays || 0) + 1; row.spec.plays = row.plays; spec.plays = row.plays;
   await db.put(row);
   if (row.plays === 2 || row.plays === 4 || row.plays % 8 === 0) rebuildBrains().catch(() => {});
@@ -150,11 +148,7 @@ state.audio.addEventListener("timeupdate", () => {                 // a loop wra
 });
 
 /* ---------- the NEXT line carries the net's guess for the track in the oven ---------- */
-const _makeJob = makeJob;
-makeJob = function (spec) {
-  const net = brainNow(); if (net) spec.guess = net.predict(spec);
-  return _makeJob(spec);
-};
+hooks.jobMade = (spec) => { const net = brainNow(); if (net) spec.guess = net.predict(spec); };
 const guessText = (spec) => spec && spec.guess != null ? ` · ${Math.round(spec.guess * 100)}% YOU` : "";
 (function () {
   const next = $("#next");
@@ -283,9 +277,7 @@ async function openTaste() {
   openTaste.redraw = show;
 }
 /* a reaction while TASTE is open: retrain, and let the neurons flare */
-const _react = react;
-react = async function (emoji, text) {
-  await _react(emoji, text);
+hooks.reacted = () => {
   rebuildBrains().then(() => {
     if ($("#taste").classList.contains("hidden") || !openTaste.redraw) return;
     let t0 = performance.now();