v0.2.0 — Phase β-1 Decks lesen

Deck-Liste mit Web-Parität: alle eigenen Decks aus cardecky-api,
Card-/Due-Counts pro Deck (Web-Pattern: separate Calls), Pull-to-
Refresh, Offline-Read via SwiftData, Inbox-Banner für Marketplace-
Forks.

- Deck-Codable-DTO mit snake_case-CodingKeys (DeckCategory,
  DeckVisibility, FsrsSettings)
- ISO8601-Date-Decoder mit Fractional-Seconds-Toleranz
- CardsAPI.listDecks() + cardCount() + dueCount()
- CachedDeck SwiftData-Model mit lastFetchedAt
- DeckListStore (API + Cache, paralleles Counts-Fetching via TaskGroup)
- DeckListView mit forest-Theme, deck.color-Streifen, Inbox-Banner
- AccountView mit Sign-out
- DashboardView durch DeckListView ersetzt
- 6 Unit-Tests + 1 UI-Test grün

Phasen-Plan: mana/docs/playbooks/CARDS_NATIVE_GREENFIELD.md

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

Tests/UnitTests/DeckDecodingTests.swift

@@ -0,0 +1,105 @@
+import Foundation
+import Testing
+@testable import CardsNative
+
+@Suite("Deck-JSON-Decoding")
+struct DeckDecodingTests {
+    @Test("Wire-Format aus toDeckDto decodet sauber")
+    func decodesDeckFromWireFormat() throws {
+        let json = """
+        {
+            "id": "01ARZ3NDEKTSV4RRFFQ69G5FAV",
+            "user_id": "user_123",
+            "name": "Spanisch A1",
+            "description": "Grundwortschatz",
+            "color": "#10803D",
+            "category": "language",
+            "visibility": "private",
+            "fsrs_settings": {"request_retention": 0.9, "maximum_interval": 365},
+            "content_hash": "abc123",
+            "forked_from_marketplace_deck_id": null,
+            "forked_from_marketplace_version_id": null,
+            "archived_at": null,
+            "created_at": "2026-05-12T10:30:00.123Z",
+            "updated_at": "2026-05-12T15:45:00.456Z"
+        }
+        """.data(using: .utf8)!
+
+        let decoder = JSONDecoder()
+        decoder.dateDecodingStrategy = .iso8601withFractional
+        let deck = try decoder.decode(Deck.self, from: json)
+
+        #expect(deck.id == "01ARZ3NDEKTSV4RRFFQ69G5FAV")
+        #expect(deck.name == "Spanisch A1")
+        #expect(deck.description == "Grundwortschatz")
+        #expect(deck.color == "#10803D")
+        #expect(deck.category == .language)
+        #expect(deck.visibility == .private)
+        #expect(deck.isFromMarketplace == false)
+        #expect(deck.archivedAt == nil)
+    }
+
+    @Test("Marketplace-Forks werden erkannt")
+    func recognizesMarketplaceFork() throws {
+        let json = """
+        {
+            "id": "deck_456",
+            "user_id": "user_123",
+            "name": "Geografie",
+            "description": null,
+            "color": null,
+            "category": null,
+            "visibility": "private",
+            "fsrs_settings": {},
+            "content_hash": null,
+            "forked_from_marketplace_deck_id": "mp_deck_789",
+            "forked_from_marketplace_version_id": "mp_ver_1",
+            "archived_at": null,
+            "created_at": "2026-05-01T00:00:00.000Z",
+            "updated_at": "2026-05-01T00:00:00.000Z"
+        }
+        """.data(using: .utf8)!
+
+        let decoder = JSONDecoder()
+        decoder.dateDecodingStrategy = .iso8601withFractional
+        let deck = try decoder.decode(Deck.self, from: json)
+
+        #expect(deck.isFromMarketplace == true)
+        #expect(deck.forkedFromMarketplaceDeckId == "mp_deck_789")
+        #expect(deck.category == nil)
+    }
+
+    @Test("DeckListResponse-Wrapper")
+    func decodesListResponse() throws {
+        let json = """
+        {
+            "decks": [
+                {
+                    "id": "d1",
+                    "user_id": "u1",
+                    "name": "Deck 1",
+                    "description": null,
+                    "color": null,
+                    "category": null,
+                    "visibility": "private",
+                    "fsrs_settings": {},
+                    "content_hash": null,
+                    "forked_from_marketplace_deck_id": null,
+                    "forked_from_marketplace_version_id": null,
+                    "archived_at": null,
+                    "created_at": "2026-01-01T00:00:00.000Z",
+                    "updated_at": "2026-01-01T00:00:00.000Z"
+                }
+            ],
+            "total": 1
+        }
+        """.data(using: .utf8)!
+
+        let decoder = JSONDecoder()
+        decoder.dateDecodingStrategy = .iso8601withFractional
+        let response = try decoder.decode(DeckListResponse.self, from: json)
+
+        #expect(response.total == 1)
+        #expect(response.decks.first?.name == "Deck 1")
+    }
+}