fix code review issues: deferral date format, storeFlags SELECT, event loop leaks, GTD selection tracking

- fix deferral resurfacing using VTODOParser.formatDateOnly instead of ISO8601 (date format mismatch)
- add SELECT mailbox before UID STORE in storeFlags (IMAP protocol requirement)
- pass credentials to SyncCoordinator so IDLE monitoring activates
- add selectedItem tracking to MailViewModel, wire List selection in GTD views
- fix startPeriodicSync to sleep-first, preventing duplicate sync on launch
- add deinit cleanup for EventLoopGroup in IMAPConnection, SMTPConnection
- use separate IMAP client for attachment downloads, avoid shared connection interference
- remove [weak self] from IMAPIdleClient actor Task to prevent orphaned connections
- fix isGTDPerspective to check selectedMailbox instead of items.isEmpty
- fix fetchBody to use complete RFC822 fetch instead of BODY[TEXT]
- reuse single IMAP connection per ActionQueue.flush() batch
- add requiresIMAP to ActionPayload for connection batching
- load task categories from label store instead of hardcoded empty array
- suppress NIOSSLHandler Sendable warnings via Package.swift unsafeFlags
- fix unused variable warnings across codebase

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

Packages/MagnumOpusCore/Sources/IMAPClient/IMAPClient.swift

@@ -152,23 +152,24 @@ public actor IMAPClient: IMAPClientProtocol {
 	}
 
 	public func fetchBody(uid: Int) async throws -> (text: String?, html: String?) {
-		guard var runner else { throw IMAPError.notConnected }
-		let uidValue = UID(rawValue: UInt32(uid))
-		let range = MessageIdentifierRange<UID>(uidValue...uidValue)
-		let set = MessageIdentifierSetNonEmpty<UID>(range: range)
-		let responses = try await runner.run(.uidFetch(
-			.set(set),
-			[.bodySection(peek: true, SectionSpecifier(kind: .text), nil)],
-			[]
-		))
-		self.runner = runner
-		return parseBodyResponse(responses)
+		// Fetch the complete RFC822 message and parse with MIME-aware logic
+		let raw = try await fetchFullMessage(uid: uid)
+		guard !raw.isEmpty else { return (text: nil, html: nil) }
+		return parseBodyResponse(raw)
 	}
 
 	// MARK: - Write operations
 
 	public func storeFlags(uid: Int, mailbox: String, add: [String], remove: [String]) async throws {
 		guard var runner else { throw IMAPError.notConnected }
+
+		// SELECT the mailbox before UID STORE — IMAP requires it
+		let selectResponses = try await runner.run(.select(MailboxName(ByteBuffer(string: mailbox))))
+		self.runner = runner
+		guard selectResponses.contains(where: { isOKTagged($0) }) else {
+			throw IMAPError.unexpectedResponse("SELECT \(mailbox) failed")
+		}
+
 		let uidValue = UID(rawValue: UInt32(uid))
 		let range = MessageIdentifierRange<UID>(uidValue...uidValue)
 		let set = MessageIdentifierSetNonEmpty<UID>(range: range)
@@ -516,28 +517,21 @@ public actor IMAPClient: IMAPClientProtocol {
 		return String(buffer: bodyBuffer)
 	}
 
-	private func parseBodyResponse(_ responses: [Response]) -> (text: String?, html: String?) {
-		var bodyBuffer = ByteBuffer()
-
-		for response in responses {
-			if case .fetch(let fetchResponse) = response {
-				switch fetchResponse {
-				case .streamingBytes(let bytes):
-					var mutableBytes = bytes
-					bodyBuffer.writeBuffer(&mutableBytes)
-				default:
-					break
-				}
-			}
+	private func parseBodyResponse(_ raw: String) -> (text: String?, html: String?) {
+		// Extract body after blank line (headers end at \r\n\r\n)
+		let bodyString: String
+		if let range = raw.range(of: "\r\n\r\n") {
+			bodyString = String(raw[range.upperBound...])
+		} else if let range = raw.range(of: "\n\n") {
+			bodyString = String(raw[range.upperBound...])
+		} else {
+			bodyString = raw
 		}
 
-		guard bodyBuffer.readableBytes > 0 else {
+		guard !bodyString.isEmpty else {
 			return (text: nil, html: nil)
 		}
 
-		let bodyString = String(buffer: bodyBuffer)
-
-		// Simple heuristic: if the body contains HTML tags, treat as HTML
 		let lowered = bodyString.lowercased()
 		if lowered.contains("<html") || lowered.contains("<body") || lowered.contains("<div") {
 			return (text: nil, html: bodyString)

Packages/MagnumOpusCore/Sources/IMAPClient/IMAPConnection.swift

@@ -1,7 +1,7 @@
 import NIO
 import NIOIMAPCore
-@preconcurrency import NIOIMAP
-@preconcurrency import NIOSSL
+import NIOIMAP
+import NIOSSL
 
 actor IMAPConnection {
 	private let host: String
@@ -17,16 +17,20 @@ actor IMAPConnection {
 		self.responseHandler = IMAPResponseHandler()
 	}
 
+	deinit {
+		try? group.syncShutdownGracefully()
+	}
+
 	func connect() async throws {
 		let sslContext = try NIOSSLContext(configuration: TLSConfiguration.makeClientConfiguration())
 		let handler = responseHandler
 		let hostname = host
 
+		nonisolated(unsafe) let sslHandler = try NIOSSLClientHandler(context: sslContext, serverHostname: hostname)
 		let bootstrap = ClientBootstrap(group: group)
 			.channelOption(ChannelOptions.socketOption(.so_reuseaddr), value: 1)
 			.channelInitializer { channel in
-				let sslHandler = try! NIOSSLClientHandler(context: sslContext, serverHostname: hostname)
-				return channel.pipeline.addHandlers([
+				channel.pipeline.addHandlers([
 					sslHandler,
 					IMAPClientHandler(),
 					handler,

Packages/MagnumOpusCore/Sources/IMAPClient/IMAPIdleClient.swift

@@ -1,8 +1,8 @@
 import Foundation
 import NIO
 import NIOIMAPCore
-@preconcurrency import NIOIMAP
-@preconcurrency import NIOSSL
+import NIOIMAP
+import NIOSSL
 import Models
 
 public actor IMAPIdleClient {
@@ -29,10 +29,9 @@ public actor IMAPIdleClient {
 		try await connectAndLogin()
 		try await selectInbox()
 
-		monitorTask = Task { [weak self] in
+		monitorTask = Task {
 			var backoffSeconds: UInt64 = 5
 			while !Task.isCancelled {
-				guard let self else { break }
 				do {
 					try await self.idleLoop(onNewMail: onNewMail)
 				} catch {
@@ -79,11 +78,11 @@ public actor IMAPIdleClient {
 
 		let responseHandler = IMAPResponseHandler()
 
+		nonisolated(unsafe) let sslHandler = try NIOSSLClientHandler(context: sslContext, serverHostname: hostname)
 		let bootstrap = ClientBootstrap(group: eventLoopGroup)
 			.channelOption(ChannelOptions.socketOption(.so_reuseaddr), value: 1)
 			.channelInitializer { channel in
-				let sslHandler = try! NIOSSLClientHandler(context: sslContext, serverHostname: hostname)
-				return channel.pipeline.addHandlers([
+				channel.pipeline.addHandlers([
 					sslHandler,
 					IMAPClientHandler(),
 					responseHandler,