Initial implementation of Fantasy Hockey watchOS app

Implemented complete TCA architecture for iOS and watchOS targets:
- Authentication flow (Sign in with Apple + Yahoo OAuth)
- OAuth token management with iCloud Key-Value Storage
- Yahoo Fantasy Sports API client with async/await
- Watch Connectivity for iPhone ↔ Watch data sync
- Complete UI for both iPhone and Watch platforms

Core features:
- Matchup score display
- Category breakdown with win/loss/tie indicators
- Roster status tracking
- Manual refresh functionality
- Persistent data caching on Watch

Technical stack:
- The Composable Architecture for state management
- Swift Concurrency (async/await, actors)
- WatchConnectivity framework
- Sign in with Apple
- OAuth 2.0 authentication flow

🤖 Generated with [Claude Code](https://claude.com/claude-code)

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

FantasyWatch/FantasyWatch Watch App Watch App/Features/Matchup/WatchMatchupFeature.swift

@@ -0,0 +1,63 @@
+//
+//  WatchMatchupFeature.swift
+//  FantasyWatch Watch App
+//
+//  Created by Claude Code
+//
+
+import ComposableArchitecture
+import Foundation
+
+@Reducer
+struct WatchMatchupFeature {
+    @ObservableState
+    struct State: Equatable {
+        var matchup: Matchup?
+        var roster: RosterStatus?
+        var lastUpdate: Date?
+        var isRefreshing = false
+    }
+
+    enum Action {
+        case onAppear
+        case receivedMatchupData(Matchup, RosterStatus, Date)
+        case refreshTapped
+        case refreshComplete
+    }
+
+    @Dependency(\.watchConnectivityClient) var watchConnectivityClient
+
+    var body: some ReducerOf<Self> {
+        Reduce { state, action in
+            switch action {
+            case .onAppear:
+                return .run { send in
+                    for await (matchup, roster, timestamp) in watchConnectivityClient.matchupUpdates() {
+                        await send(.receivedMatchupData(matchup, roster, timestamp))
+                    }
+                }
+
+            case let .receivedMatchupData(matchup, roster, timestamp):
+                state.matchup = matchup
+                state.roster = roster
+                state.lastUpdate = timestamp
+                state.isRefreshing = false
+                return .none
+
+            case .refreshTapped:
+                state.isRefreshing = true
+                return .run { send in
+                    try await watchConnectivityClient.requestRefresh()
+                    try await Task.sleep(for: .seconds(2))
+                    await send(.refreshComplete)
+                } catch: { error, send in
+                    await send(.refreshComplete)
+                }
+
+            case .refreshComplete:
+                state.isRefreshing = false
+                return .none
+            }
+        }
+    }
+}