Rewrite dashboard and overlay, single /events stream, static client served by the backend

Backend: one SSE stream for messages, selection, poll and connection status; reconnect with backoff; no on-disk Innertube session cache; mock only with MOCK_CHAT=1; binds to 127.0.0.1; serves client/out so production runs on one port. Full URLs for links YouTube truncates in chat.

Client: components split out, Lucide icons, stream title and status, on-air strip, search, pause, keyboard shortcuts, overlay settings dialog. Overlay themes, position, size, animation and auto-hide via URL, sized for 1080p and scaled with the source. New blueprint theme for the brand background.

Removed Tailwind, better-sqlite3, zod, the timezone helpers, Cline memory bank and AGENTS.md. Added ESLint, node:test tests and CI.

client/lib/format.ts

@@ -0,0 +1,27 @@
+export function formatTime(iso: string): string {
+  const date = new Date(iso);
+  if (Number.isNaN(date.getTime())) return '';
+  return date.toLocaleTimeString([], { hour: '2-digit', minute: '2-digit' });
+}
+
+const URL_PATTERN = /(https?:\/\/[^\s<>"']+)/gi;
+
+export type TextPart = { type: 'text' | 'link'; content: string };
+
+/** Splits plain text into text and link parts. Used only for runs YouTube did not mark as links. */
+export function splitLinks(text: string): TextPart[] {
+  const parts: TextPart[] = [];
+  let last = 0;
+  for (const match of text.matchAll(URL_PATTERN)) {
+    const index = match.index ?? 0;
+    if (index > last) parts.push({ type: 'text', content: text.slice(last, index) });
+    parts.push({ type: 'link', content: match[0] });
+    last = index + match[0].length;
+  }
+  if (last < text.length) parts.push({ type: 'text', content: text.slice(last) });
+  return parts;
+}
+
+export function formatAmount(amount: string, currency: string): string {
+  return currency ? `${currency} ${amount}` : amount;
+}