Finish coordinator migration: zero ChatViewModel back-references remain

ChatPeerListCoordinator, ChatComposerCoordinator, ChatOutgoingCoordinator,
and GeoChannelCoordinator complete the migration; every coordinator now
depends on a narrow @MainActor context protocol. GeoChannelCoordinator's
three injected closures collapse into a weak context. New intent op
recordPublicActivity(forChannelKey:) keeps lastPublicActivityAt
single-writer. 15 new mock-context tests; flaky-poll deadline in the
gift-wrap dedup test raised for parallel load.

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

bitchatTests/ChatOutgoingCoordinatorContextTests.swift

@@ -0,0 +1,221 @@
+//
+// ChatOutgoingCoordinatorContextTests.swift
+// bitchatTests
+//
+// Exercises `ChatOutgoingCoordinator` against a mock `ChatOutgoingContext` —
+// proving the coordinator works without a `ChatViewModel`, following the
+// `ChatDeliveryCoordinatorContextTests` exemplar.
+//
+// Scope note: the geohash path builds and signs a real Nostr event via
+// `NostrProtocol.createEphemeralGeohashEvent` (pure crypto, no shared state);
+// everything else flows through the mock context.
+//
+
+import Testing
+import Foundation
+import BitFoundation
+@testable import bitchat
+
+// MARK: - Mock Context
+
+/// Lightweight stand-in for `ChatOutgoingContext` proving that
+/// `ChatOutgoingCoordinator` is testable without a `ChatViewModel`.
+@MainActor
+private final class MockChatOutgoingContext: ChatOutgoingContext {
+    // Identity & channel state
+    var nickname = "me"
+    var myPeerID = PeerID(str: "0011223344556677")
+    var activeChannel: ChannelID = .mesh
+    var selectedPrivateChatPeer: PeerID?
+    var isTeleported = false
+
+    // Commands & private messages
+    var selectedPeerAfterUpdate: PeerID??
+    private(set) var handledCommands: [String] = []
+    private(set) var updatePrivateChatPeerIfNeededCount = 0
+    private(set) var sentPrivateMessages: [(content: String, peerID: PeerID)] = []
+
+    func handleCommand(_ command: String) { handledCommands.append(command) }
+
+    func updatePrivateChatPeerIfNeeded() {
+        updatePrivateChatPeerIfNeededCount += 1
+        if let selectedPeerAfterUpdate {
+            selectedPrivateChatPeer = selectedPeerAfterUpdate
+        }
+    }
+
+    func sendPrivateMessage(_ content: String, to peerID: PeerID) {
+        sentPrivateMessages.append((content, peerID))
+    }
+
+    // Public timeline (local echo)
+    private(set) var appendedTimelineMessages: [(message: BitchatMessage, channel: ChannelID)] = []
+    private(set) var refreshedChannels: [ChannelID?] = []
+    private(set) var trimMessagesIfNeededCount = 0
+    private(set) var systemMessages: [String] = []
+
+    func parseMentions(from content: String) -> [String] {
+        content.contains("@bob") ? ["bob"] : []
+    }
+
+    func appendTimelineMessage(_ message: BitchatMessage, to channel: ChannelID) {
+        appendedTimelineMessages.append((message, channel))
+    }
+
+    func refreshVisibleMessages(from channel: ChannelID?) { refreshedChannels.append(channel) }
+    func trimMessagesIfNeeded() { trimMessagesIfNeededCount += 1 }
+    func addSystemMessage(_ content: String) { systemMessages.append(content) }
+
+    // Content dedup
+    private(set) var recordedContentKeys: [(key: String, timestamp: Date)] = []
+
+    func normalizedContentKey(_ content: String) -> String { "key:\(content)" }
+    func recordContentKey(_ key: String, timestamp: Date) {
+        recordedContentKeys.append((key, timestamp))
+    }
+
+    // Outbound routing
+    private(set) var recordedActivityKeys: [String] = []
+    private(set) var sentMeshMessages: [(content: String, mentions: [String], messageID: String, timestamp: Date)] = []
+    private(set) var sentGeohashContexts: [ChatViewModel.GeoOutgoingContext] = []
+
+    func recordPublicActivity(forChannelKey key: String) { recordedActivityKeys.append(key) }
+
+    func sendMeshMessage(_ content: String, mentions: [String], messageID: String, timestamp: Date) {
+        sentMeshMessages.append((content, mentions, messageID, timestamp))
+    }
+
+    func sendGeohash(context: ChatViewModel.GeoOutgoingContext) {
+        sentGeohashContexts.append(context)
+    }
+
+    // Geohash identity
+    struct IdentityUnavailable: Error {}
+    var deriveNostrIdentityError: Error?
+    static let dummyIdentity = NostrIdentity(
+        privateKey: Data(repeating: 0x11, count: 32),
+        publicKey: Data(repeating: 0x22, count: 32),
+        npub: "npub1mock",
+        createdAt: Date(timeIntervalSince1970: 0)
+    )
+
+    func deriveNostrIdentity(forGeohash geohash: String) throws -> NostrIdentity {
+        if let deriveNostrIdentityError { throw deriveNostrIdentityError }
+        return Self.dummyIdentity
+    }
+}
+
+// MARK: - Helpers
+
+/// Lets the coordinator's internal `Task { @MainActor … }` hops run.
+@MainActor
+private func drainMainActorTasks() async {
+    for _ in 0..<10 { await Task.yield() }
+}
+
+// MARK: - Coordinator Tests Against Mock Context
+
+/// Exercises `ChatOutgoingCoordinator` against `MockChatOutgoingContext` with
+/// no `ChatViewModel`.
+struct ChatOutgoingCoordinatorContextTests {
+
+    @Test @MainActor
+    func sendMessage_routesSlashCommandsAndDropsEmptyContent() async {
+        let context = MockChatOutgoingContext()
+        let coordinator = ChatOutgoingCoordinator(context: context)
+
+        coordinator.sendMessage("   ")
+        coordinator.sendMessage("/who all")
+        await drainMainActorTasks()
+
+        #expect(context.handledCommands == ["/who all"])
+        #expect(context.appendedTimelineMessages.isEmpty)
+        #expect(context.sentMeshMessages.isEmpty)
+    }
+
+    @Test @MainActor
+    func sendMessage_inPrivateChat_reResolvesPeerBeforeSending() async {
+        let context = MockChatOutgoingContext()
+        let coordinator = ChatOutgoingCoordinator(context: context)
+        let shortPeer = PeerID(str: "1111111111111111")
+        let stablePeer = PeerID(str: String(repeating: "ab", count: 32))
+
+        // The selected peer is refreshed (short → stable) before sending.
+        context.selectedPrivateChatPeer = shortPeer
+        context.selectedPeerAfterUpdate = stablePeer
+        coordinator.sendMessage("hi there")
+        #expect(context.updatePrivateChatPeerIfNeededCount == 1)
+        #expect(context.sentPrivateMessages.map(\.peerID) == [stablePeer])
+        #expect(context.sentPrivateMessages.map(\.content) == ["hi there"])
+
+        // If the refresh clears the selection, nothing is sent.
+        context.selectedPeerAfterUpdate = PeerID??.some(nil)
+        coordinator.sendMessage("dropped")
+        await drainMainActorTasks()
+        #expect(context.sentPrivateMessages.count == 1)
+        #expect(context.appendedTimelineMessages.isEmpty)
+    }
+
+    @Test @MainActor
+    func sendMessage_onMesh_appendsLocalEchoRecordsActivityAndSends() async {
+        let context = MockChatOutgoingContext()
+        let coordinator = ChatOutgoingCoordinator(context: context)
+
+        coordinator.sendMessage("  hello @bob  ")
+        await drainMainActorTasks()
+
+        // Local echo uses the trimmed content, own nickname/peer ID, mentions.
+        #expect(context.appendedTimelineMessages.count == 1)
+        let echo = context.appendedTimelineMessages[0]
+        #expect(echo.message.content == "hello @bob")
+        #expect(echo.message.sender == "me")
+        #expect(echo.message.senderPeerID == context.myPeerID)
+        #expect(echo.message.mentions == ["bob"])
+        #expect(echo.channel == .mesh)
+        #expect(context.refreshedChannels == [.mesh])
+        #expect(context.recordedContentKeys.map(\.key) == ["key:hello @bob"])
+        #expect(context.trimMessagesIfNeededCount == 1)
+
+        // The mesh send carries the original (untrimmed) content and reuses
+        // the echo's message ID and timestamp; activity is stamped for "mesh".
+        #expect(context.recordedActivityKeys == ["mesh"])
+        #expect(context.sentMeshMessages.count == 1)
+        let sent = context.sentMeshMessages[0]
+        #expect(sent.content == "  hello @bob  ")
+        #expect(sent.mentions == ["bob"])
+        #expect(sent.messageID == echo.message.id)
+        #expect(sent.timestamp == echo.message.timestamp)
+    }
+
+    @Test @MainActor
+    func sendMessage_onLocationChannel_sendsGeohashEventOrFailsWithSystemMessage() async {
+        let context = MockChatOutgoingContext()
+        let coordinator = ChatOutgoingCoordinator(context: context)
+        let channel = GeohashChannel(level: .city, geohash: "u4pruydq")
+        context.activeChannel = .location(channel)
+        context.isTeleported = true
+
+        coordinator.sendMessage("hello geo")
+        await drainMainActorTasks()
+
+        // Local echo carries the geohash sender suffix (#last-4-of-pubkey) and
+        // the signed event's ID; the send context targets the same channel.
+        #expect(context.appendedTimelineMessages.count == 1)
+        let echo = context.appendedTimelineMessages[0].message
+        #expect(echo.sender == "me#2222")
+        #expect(context.recordedActivityKeys == ["geo:u4pruydq"])
+        #expect(context.sentGeohashContexts.count == 1)
+        let geoContext = context.sentGeohashContexts[0]
+        #expect(geoContext.channel == channel)
+        #expect(geoContext.teleported)
+        #expect(geoContext.event.id == echo.id)
+
+        // Identity derivation failure: system message, no echo, no send.
+        context.deriveNostrIdentityError = MockChatOutgoingContext.IdentityUnavailable()
+        coordinator.sendMessage("doomed")
+        await drainMainActorTasks()
+        #expect(context.systemMessages.count == 1)
+        #expect(context.appendedTimelineMessages.count == 1)
+        #expect(context.sentGeohashContexts.count == 1)
+    }
+}