feat: Phase 1.5 — health prober, Oracle's Memory, off-thread EPG, PWA

Resilience + scale pass on top of the v1 core.

Stream health prober:
- New SSRF-validated /probe endpoint (HEAD -> ranged-GET fallback, 6s timeout,
  5-min TTL cache, concurrency-capped, no-store) + orb_probe_total metrics
- Front-end health.js: lazy bounded-concurrency probing (current + sampled
  channels, not the whole catalog), LIVE/DEGRADED/DEAD scoring, guide skull
  glyph, instant no-signal on zap to a known-dead channel

Oracle's Memory (memory.js):
- Session resurrection (last channel, volume, mute, theater/dim/ambient)
- Exponential-decay per-channel uptime history; pinning; dead-channel auto-skip

Off-thread XMLTV:
- lib/xmltv-parse.js (pure, hand-rolled scanner, no DOMParser/regex backtracking)
  run in epg-worker.js module worker; wired into the iptv-org provider
- Unit-tested in node: entity decode, TZ offsets, 20k programmes off-thread

Service worker / PWA:
- manifest.webmanifest + orb icons; sw.js (cache-first shell + hls.js,
  stale-while-revalidate for JSON-over-relay, never caches streams)
- CSP gains worker-src + manifest-src; relay sends no-store on /relay + /probe
  so the SW is the sole metadata freshness authority; webmanifest MIME fix

Docs: README de-emojified (title only) and reframed as a peer parallel build.

Verified: SSRF probes blocked, legit probe + cache, new headers present,
PWA assets served, parser tests 8/8, JS syntax clean, zero Rust warnings.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

web/player.js

@@ -1,5 +1,7 @@
 // player.js — HLS.js wiring, live-aware ghost controls, dead-stream handling.
 
+import { memory } from './memory.js';
+
 const HLS_CONFIG = {
   enableWorker: true,
   lowLatencyMode: false,
@@ -171,6 +173,7 @@ export class Player {
     const m = this.video.muted || this.video.volume === 0;
     this.els.btnMute.textContent = m ? '🔇' : '🔊';
     this.els.btnMute.setAttribute('aria-pressed', String(m));
+    memory.rememberVolume(this.video.volume, this.video.muted);
   }
   setVolume(delta) {
     this.video.muted = false;