The page's script is TypeScript in web/src, built and minified with swc

- web/src/*.ts: the script that was inline in index.html and login.html, split along its
  existing sections. Still one scope, concatenated in order, not modules.
- web/build.mjs strips the types, puts the script in the page and minifies it with swc;
  build.rs runs it into OUT_DIR and web.rs include_str!s the result. 137 KB -> 106 KB.
- npx tsc -p . type-checks web/src, loosely; the handful of annotations it needed
  change no behaviour.
- The Docker build installs node and swc (npm ci --omit=dev).
- Two list requests racing no longer let the older one win, and switching tabs clears
  the selection it closes, which made a browser test flaky.

Closes #23, #24.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

web/src/events.ts

@@ -0,0 +1,46 @@
+/* ---------------- live events ---------------- */
+let sse;
+function connect(){
+  sse=new EventSource('/api/events');
+  const soon=(fn,ms=500)=>{ let t; return ()=>{ clearTimeout(t); t=setTimeout(fn,ms); }; };
+  const refreshFeeds=soon(()=>loadFeeds(true));
+  const refreshEntries=soon(()=>{ if(S.feed) loadEntries(); });
+  let fresh={};
+  const tellNew=soon(()=>{
+    const feeds=Object.keys(fresh), n=feeds.reduce((a,k)=>a+fresh[k],0);
+    if(n) toast(feeds.length===1 ? `${feeds[0]}: ${n} new` : `${n} new in ${feeds.length} feeds`);
+    fresh={};
+  },900);
+  sse.onmessage=m=>{
+    let ev; try{ ev=JSON.parse(m.data) }catch{ return }
+    if(ev.ev==='progress'){
+      const pct=ev.total?ev.done/ev.total*100:0;
+      // Only the row actually downloading. Without the enclosure id this used to paint
+      // every pending bar at once, so adding a feed looked like it was fetching the lot.
+      const bar=document.querySelector<HTMLElement>(`.dlbar[data-bar="${ev.enclosure}"] i`);
+      if(bar){ bar.style.width=pct+'%'; bar.parentElement.classList.add('live'); }
+      $('#count') && ($('#count').textContent=`downloading ${ev.file} — ${pct.toFixed(0)}%`);
+    }
+    else if(ev.ev==='download_done'){
+      const bar=document.querySelector(`.dlbar[data-bar="${ev.enclosure}"]`);
+      if(bar) bar.classList.remove('live');
+      toast('Downloaded '+ev.path.split('/').pop()); refreshEntries(); refreshFeeds();
+    }
+    else if(ev.ev==='download_error'){
+      const bar=document.querySelector(`.dlbar[data-bar="${ev.enclosure}"]`);
+      if(bar) bar.classList.remove('live');
+      toast('Download failed: '+ev.msg,true); refreshEntries();
+    }
+    else if(ev.ev==='feed_done'){
+      if(ev.new){ fresh[ev.feed]=(fresh[ev.feed]||0)+ev.new; tellNew(); }
+      refreshFeeds(); if(ev.feed===S.feed||S.feed===':all') refreshEntries();
+    }
+    // No toast: a scan of every feed raised one per failure, to everyone. The feed list's
+    // red ! marks the feed instead, and its page says why.
+    else if(ev.ev==='feed_error') refreshFeeds();
+    else if(ev.ev==='scan_done'){ refreshFeeds(); refreshEntries(); }
+  };
+  sse.onerror=()=>{ sse.close(); setTimeout(connect,4000); };
+}
+connect();
+loadFeeds();