fix(decks): align due card count with study screen limits

The deck list was showing all due cards without applying the
newCardsPerDay limit or review card limit (100), causing a mismatch
with the actual number of cards available in the study screen.

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

3 files changed, 36 insertions, 0 deletions

diff --git a/src/server/repositories/card.test.ts b/src/server/repositories/card.test.ts
index 1ed31c7..21e5485 100644
--- a/src/server/repositories/card.test.ts
+++ b/src/server/repositories/card.test.ts
@@ -112,6 +112,8 @@ function createMockCardRepo(): CardRepository {
 		softDeleteByNoteId: vi.fn(),
 		findDueCards: vi.fn(),
 		countDueCards: vi.fn(),
+		countDueNewCards: vi.fn(),
+		countDueReviewCards: vi.fn(),
 		findDueCardsWithNoteData: vi.fn(),
 		findDueCardsForStudy: vi.fn(),
 		findDueNewCardsForStudy: vi.fn(),
diff --git a/src/server/repositories/card.ts b/src/server/repositories/card.ts
index f546922..d382f4d 100644
--- a/src/server/repositories/card.ts
+++ b/src/server/repositories/card.ts
@@ -221,6 +221,38 @@ export const cardRepository: CardRepository = {
 		return result[0]?.count ?? 0;
 	},
 
+	async countDueNewCards(deckId: string, now: Date): Promise<number> {
+		const boundary = getEndOfStudyDayBoundary(now);
+		const result = await db
+			.select({ count: sql<number>`count(*)::int` })
+			.from(cards)
+			.where(
+				and(
+					eq(cards.deckId, deckId),
+					isNull(cards.deletedAt),
+					lt(cards.due, boundary),
+					eq(cards.state, CardState.New),
+				),
+			);
+		return result[0]?.count ?? 0;
+	},
+
+	async countDueReviewCards(deckId: string, now: Date): Promise<number> {
+		const boundary = getEndOfStudyDayBoundary(now);
+		const result = await db
+			.select({ count: sql<number>`count(*)::int` })
+			.from(cards)
+			.where(
+				and(
+					eq(cards.deckId, deckId),
+					isNull(cards.deletedAt),
+					lt(cards.due, boundary),
+					ne(cards.state, CardState.New),
+				),
+			);
+		return result[0]?.count ?? 0;
+	},
+
 	async findDueCardsWithNoteData(
 		deckId: string,
 		now: Date,
diff --git a/src/server/repositories/types.ts b/src/server/repositories/types.ts
index 47fb68f..4042daf 100644
--- a/src/server/repositories/types.ts
+++ b/src/server/repositories/types.ts
@@ -168,6 +168,8 @@ export interface CardRepository {
 		now: Date,
 		limit: number,
 	): Promise<CardForStudy[]>;
+	countDueNewCards(deckId: string, now: Date): Promise<number>;
+	countDueReviewCards(deckId: string, now: Date): Promise<number>;
 	updateFSRSFields(
 		id: string,
 		deckId: string,