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>

doc/research/reference-sources/wf_FloatplaneAPIClient+Extensions.swift

@@ -0,0 +1,125 @@
+import Foundation
+import CoreGraphics
+import SwiftUI
+import FloatplaneAPIClient
+
+extension ErrorModel: LocalizedError {
+	public var errorDescription: String? {
+		let message = self.message ?? self.errors.first?.message ?? self.errors.first?.name ?? "Error message unretrievable."
+		let separator: String
+		if message.last != "." {
+			separator = ". "
+		} else {
+			separator = " "
+		}
+		return message + separator + "Error ID: " + self.id
+	}
+	
+	public var failureReason: String? {
+		nil
+	}
+
+	public var recoverySuggestion: String? {
+		nil
+	}
+
+	public var helpAnchor: String? {
+		nil
+	}
+}
+
+extension VideoAttachmentModel: Identifiable { }
+
+extension PictureAttachmentModel: Identifiable { }
+
+extension AudioAttachmentModel: Identifiable { }
+
+extension BlogPostModelV3: Identifiable { }
+
+extension UserSubscriptionModel: Identifiable {
+	public var id: String {
+		self.creator
+	}
+}
+
+protocol ImageModelShared {
+	var width: Int { get set }
+	var height: Int { get set }
+	var path: String { get set }
+	var childImages: [ChildImageModel]? { get set }
+}
+
+extension ImageModelShared {
+	var aspectRatio: CGFloat {
+		return CGFloat(self.width) / CGFloat(self.height)
+	}
+	
+	func bestImage(for geometrySize: CGSize?) -> URL? {
+		guard let geometrySize else {
+			return nil
+		}
+		
+		let geometryMagnitude = Int(geometrySize.width * geometrySize.height)
+		var difference = (self.width * self.height) - geometryMagnitude
+		var path = self.path
+		
+		for childImage in self.childImages ?? [] {
+			let childDifference = (childImage.width * childImage.height) - geometryMagnitude
+			
+			if childDifference >= 0 && childDifference < difference {
+				difference = childDifference
+				path = childImage.path
+			}
+		}
+		
+		return URL(string: path)
+	}
+}
+
+extension ImageModel: ImageModelShared {
+}
+
+extension Optional where Wrapped == ImageModelShared {
+	var pathUrlOrNil: URL? {
+		if let thumbnail = self {
+			return URL(string: thumbnail.path)
+		} else {
+			return nil
+		}
+	}
+	
+	func bestImage(for geometrySize: CGSize?) -> URL? {
+		if let thumbnail = self {
+			return thumbnail.bestImage(for: geometrySize)
+		} else {
+			return nil
+		}
+	}
+}
+
+extension BlogPostModelV3Channel {
+	var asChannelModel: ChannelModel? {
+		switch self {
+		case let .typeChannelModel(channelModel):
+			return channelModel
+		default:
+			return nil
+		}
+	}
+}
+
+extension BlogPostModelV3 {
+	var firstVideoAttachmentId: String? {
+		return self.attachmentOrder.filter({ self.videoAttachments?.contains($0) == true }).first
+	}
+}
+
+extension ContentPostV3Response {
+	var firstVideoAttachmentId: String? {
+		return self.attachmentOrder.filter({ self.videoAttachments?.lazy.map(\.id).contains($0) == true }).first
+	}
+
+	var firstVideoAttachment: VideoAttachmentModel? {
+		return self.videoAttachments?.first(where: { $0.id == firstVideoAttachmentId })
+	}
+}