feat(domain): add DynamicSport model for CloudKit-defined sports

Struct representing sports synced from CloudKit. Conforms to AnySport
protocol for interchangeable use with Sport enum in UI and planning.

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

SportsTime/Core/Models/Domain/DynamicSport.swift

@@ -0,0 +1,50 @@
+//
+//  DynamicSport.swift
+//  SportsTime
+//
+//  Domain model for CloudKit-defined sports.
+//
+
+import SwiftUI
+
+/// A sport defined via CloudKit, as opposed to the hardcoded Sport enum.
+/// Conforms to AnySport for interchangeable use with Sport enum.
+nonisolated struct DynamicSport: Identifiable, Hashable, Codable, Sendable {
+    let id: String
+    let abbreviation: String
+    let displayName: String
+    let iconName: String
+    let colorHex: String
+    let seasonStartMonth: Int
+    let seasonEndMonth: Int
+
+    init(
+        id: String,
+        abbreviation: String,
+        displayName: String,
+        iconName: String,
+        colorHex: String,
+        seasonStartMonth: Int,
+        seasonEndMonth: Int
+    ) {
+        self.id = id
+        self.abbreviation = abbreviation
+        self.displayName = displayName
+        self.iconName = iconName
+        self.colorHex = colorHex
+        self.seasonStartMonth = seasonStartMonth
+        self.seasonEndMonth = seasonEndMonth
+    }
+}
+
+// MARK: - AnySport Conformance
+
+extension DynamicSport: AnySport {
+    var sportId: String { id }
+
+    var color: Color { Color(hex: colorHex) }
+
+    var seasonMonths: (start: Int, end: Int) {
+        (seasonStartMonth, seasonEndMonth)
+    }
+}

SportsTimeTests/Domain/DynamicSportTests.swift

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+//
+//  DynamicSportTests.swift
+//  SportsTimeTests
+//
+
+import Testing
+import SwiftUI
+@testable import SportsTime
+
+@Suite("DynamicSport")
+struct DynamicSportTests {
+
+    @Test("DynamicSport conforms to AnySport protocol")
+    func dynamicSportConformsToAnySport() {
+        let xfl = DynamicSport(
+            id: "xfl",
+            abbreviation: "XFL",
+            displayName: "XFL Football",
+            iconName: "football.fill",
+            colorHex: "#E31837",
+            seasonStartMonth: 2,
+            seasonEndMonth: 5
+        )
+
+        let sport: any AnySport = xfl
+        #expect(sport.sportId == "xfl")
+        #expect(sport.displayName == "XFL Football")
+        #expect(sport.iconName == "football.fill")
+    }
+
+    @Test("DynamicSport color parses from hex")
+    func dynamicSportColorParsesFromHex() {
+        let sport = DynamicSport(
+            id: "test",
+            abbreviation: "TST",
+            displayName: "Test Sport",
+            iconName: "star.fill",
+            colorHex: "#FF0000",
+            seasonStartMonth: 1,
+            seasonEndMonth: 12
+        )
+
+        // Color should be red
+        #expect(sport.color != Color.clear)
+    }
+
+    @Test("DynamicSport isInSeason works correctly")
+    func dynamicSportIsInSeason() {
+        let xfl = DynamicSport(
+            id: "xfl",
+            abbreviation: "XFL",
+            displayName: "XFL Football",
+            iconName: "football.fill",
+            colorHex: "#E31837",
+            seasonStartMonth: 2,
+            seasonEndMonth: 5
+        )
+
+        // March is in XFL season (Feb-May)
+        let march = Calendar.current.date(from: DateComponents(year: 2026, month: 3, day: 15))!
+        #expect(xfl.isInSeason(for: march))
+
+        // September is not in XFL season
+        let september = Calendar.current.date(from: DateComponents(year: 2026, month: 9, day: 15))!
+        #expect(!xfl.isInSeason(for: september))
+    }
+
+    @Test("DynamicSport is Hashable")
+    func dynamicSportIsHashable() {
+        let sport1 = DynamicSport(
+            id: "xfl",
+            abbreviation: "XFL",
+            displayName: "XFL Football",
+            iconName: "football.fill",
+            colorHex: "#E31837",
+            seasonStartMonth: 2,
+            seasonEndMonth: 5
+        )
+
+        let sport2 = DynamicSport(
+            id: "xfl",
+            abbreviation: "XFL",
+            displayName: "XFL Football",
+            iconName: "football.fill",
+            colorHex: "#E31837",
+            seasonStartMonth: 2,
+            seasonEndMonth: 5
+        )
+
+        let set: Set<DynamicSport> = [sport1, sport2]
+        #expect(set.count == 1)
+    }
+
+    @Test("DynamicSport is Codable")
+    func dynamicSportIsCodable() throws {
+        let original = DynamicSport(
+            id: "xfl",
+            abbreviation: "XFL",
+            displayName: "XFL Football",
+            iconName: "football.fill",
+            colorHex: "#E31837",
+            seasonStartMonth: 2,
+            seasonEndMonth: 5
+        )
+
+        let encoded = try JSONEncoder().encode(original)
+        let decoded = try JSONDecoder().decode(DynamicSport.self, from: encoded)
+
+        #expect(decoded.id == original.id)
+        #expect(decoded.abbreviation == original.abbreviation)
+        #expect(decoded.displayName == original.displayName)
+    }
+}