perf: faster stream startup

- Stop sending no-store on vendored player libraries: hls.min.js and
  mpegts.min.js (~750 KB) were re-downloaded on every player open
- hls.js: start with 1 live segment instead of 3, lower buffer-first
  threshold 1.5s -> 0.8s, poll buffer every 100ms
- mpegts.js: initial stash 512KB -> 128KB, start at 0.5s buffered
- Live FFmpeg: -hls_init_time 1 closes the first segment after ~1s

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

.claude/settings.json

@@ -0,0 +1,5 @@
+{
+  "enabledPlugins": {
+    "frontend-design@claude-plugins-official": true
+  }
+}