Plugin-scoped CancellationTokenSource fließt jetzt durch LoadAsync und
die Texture-Calls; Dispose cancelt in-flight downloads. Smoke (System-
Spam + Reload) sauber, weiter beobachten unter höherem Emote-Volumen.
- EmoteCache.cs replaces the per-call "new HttpClient()" with the
existing static Client field. The static instance already exists
for two other endpoints in the same file and reuses connection
pooling; the third call site was a stray that leaked a socket
on every emote download
- FontManager.cs wraps both the HttpClient and the HttpResponseMessage
in using-blocks, replaces the .Result/AggregateException sandwich
with GetAwaiter().GetResult() for clean exception propagation, and
adds EnsureSuccessStatusCode so failed downloads don't silently
produce a zero-byte font file. Full async refactor of the FontManager
constructor is tracked separately
JonKazama-Hellion