Split app.js into one script per feature; versioning covers every public file; README for the new features

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

tools/player-test.js

@@ -1,6 +1,6 @@
 const fs=require('fs'), vm=require('vm');
-const src=fs.readFileSync(''+require('path').join(__dirname,'..','public','app.js')+'','utf8');
-const a=src.indexOf("const shuffled = a =>"), b=src.indexOf("// ---- People (admin)");
+const src=['music.js','player.js','lyrics-view.js'].map(f=>fs.readFileSync(require('path').join(__dirname,'..','public',f),'utf8')).join('\n');
+const a=src.indexOf("const shuffled = a =>"), b=src.length;
 let code=src.slice(a,b);
 const listeners={};
 class FakeAudio{constructor(){this.paused=true;this.currentTime=0;this.duration=100;this.readyState=4;this.error=null;this._l={};this.src='';}
@@ -8,7 +8,7 @@ class FakeAudio{constructor(){this.paused=true;this.currentTime=0;this.duration=
  play(){this.paused=false;this.fire('play');return Promise.resolve()} pause(){if(!this.paused){this.paused=true;this.fire('pause')}} getAttribute(){return this.src||null} load(){}}
 const toasts=[];const store={d:{},get(k,d){return this.d[k]??d},set(k,v){this.d[k]=v},del(k){delete this.d[k]}};
 const el=()=>({remove(){},classList:{toggle(){},add(){}},setAttribute(){},dataset:{},style:{},querySelector:()=>el(),querySelectorAll:()=>[],set innerHTML(v){},set textContent(v){}});
-const ctx={Audio:FakeAudio,store,toast:m=>toasts.push(m),px:{art:()=>'x'},icon:()=>'',esc:s=>s,fmtDur:()=>'',$:()=>el(),document:{querySelectorAll:()=>[],querySelector:()=>null},allowed:()=>true,
+const ctx={sleepT:{eot:false},sleepClear(){},Audio:FakeAudio,store,toast:m=>toasts.push(m),px:{art:()=>'x'},icon:()=>'',esc:s=>s,fmtDur:()=>'',$:()=>el(),document:{querySelectorAll:()=>[],querySelector:()=>null},allowed:()=>true,
  navigator:{onLine:true},addEventListener:(e,f)=>{listeners[e]=f},setTimeout,clearTimeout,fetch:()=>new Promise(()=>{}),URL:{createObjectURL:()=>'blob:x',revokeObjectURL(){}},
  Image:class{},MediaMetadata:class{},openSheet:()=>({}),closeSheet(){},actionSheet(){},Response,URLSearchParams,AbortController,Promise,Set,Map,Date,Math,saveStateHook:0,location:{hash:'#/tasks'}};
 vm.createContext(ctx); vm.runInContext(code+";this.pl=pl;this.next=next;this.prev=prev;this.setShuffle=setShuffle;this.setRepeat=setRepeat;this.playQueue=playQueue;this.advance=advance;this.cur=cur;this.recover=recover;this.srcOf=srcOf;",ctx);