Floatplane channel plugin for Jellyfin 10.10.x: browse, HLS proxy, cookie session, CI release

- IChannel: creators -> sub-channels -> video posts (public listing API, search mapped)
- IRequiresMediaInfoCallback -> signed proxy URLs; stream controller rewrites HLS so the
  AES-128 key is fetched server-side with the session cookie, segments stay on the CDN
- delivery/info cached per token lifetime and throttled (~2/min)
- config page: paste sails.sid + validate, extra creators, quality, search test
- scripts/package.sh -> plugin folder + zip + md5 + manifest.json; Gitea release workflow
- research docs, HAR analysis (HAR itself gitignored), install-pi5.sh

Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>

Jellyfin.Plugin.Floatplane/PluginServiceRegistrator.cs

@@ -0,0 +1,50 @@
+using System;
+using System.Net.Http;
+using Jellyfin.Plugin.Floatplane.Api;
+using Jellyfin.Plugin.Floatplane.Channel;
+using Jellyfin.Plugin.Floatplane.Playback;
+using MediaBrowser.Controller;
+using MediaBrowser.Controller.Channels;
+using MediaBrowser.Controller.Plugins;
+using Microsoft.Extensions.DependencyInjection;
+
+namespace Jellyfin.Plugin.Floatplane;
+
+/// <summary>
+/// Registers the plugin's services. Found by Jellyfin through type scanning; needs a
+/// parameterless constructor. In 10.10 <c>ChannelManager</c> takes <c>IEnumerable&lt;IChannel&gt;</c>
+/// from DI, so the channel must be registered here.
+/// </summary>
+public class PluginServiceRegistrator : IPluginServiceRegistrator
+{
+    /// <summary>Named HttpClient for Floatplane API + CDN traffic.</summary>
+    public const string HttpClientName = "Floatplane";
+
+    /// <inheritdoc />
+    public void RegisterServices(IServiceCollection serviceCollection, IServerApplicationHost applicationHost)
+    {
+        serviceCollection
+            .AddHttpClient(HttpClientName, client =>
+            {
+                client.Timeout = TimeSpan.FromSeconds(60);
+                client.DefaultRequestHeaders.UserAgent.ParseAdd(Plugin.UserAgent);
+            })
+            .ConfigurePrimaryHttpMessageHandler(() => new HttpClientHandler
+            {
+                // The session cookie is attached per request; no cookie jar, no redirects
+                // (a 302 from the CDN would otherwise be followed with the cookie attached).
+                UseCookies = false,
+                AllowAutoRedirect = false,
+                AutomaticDecompression = System.Net.DecompressionMethods.All
+            });
+
+        serviceCollection.AddSingleton<FloatplaneApiClient>();
+        serviceCollection.AddSingleton<CatalogService>();
+        serviceCollection.AddSingleton<DeliveryResolver>();
+
+        // One instance: the status endpoint and the sync task must see the same caches
+        // as the channel Jellyfin serves from.
+        serviceCollection.AddSingleton<FloatplaneChannel>();
+        serviceCollection.AddSingleton<IChannel>(sp => sp.GetRequiredService<FloatplaneChannel>());
+    }
+}