feat(server): add study session API with FSRS integration

Implement study endpoints for spaced repetition learning:
- GET /api/decks/:deckId/study to fetch due cards
- POST /api/decks/:deckId/study/:cardId to submit reviews
- Integrate ts-fsrs library for scheduling algorithm
- Add ReviewLog repository for tracking review history

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

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

1 files changed, 3 insertions, 2 deletions

diff --git a/src/server/index.ts b/src/server/index.ts
index d00564f..0391119 100644
--- a/src/server/index.ts
+++ b/src/server/index.ts
@@ -2,7 +2,7 @@ import { serve } from "@hono/node-server";
 import { Hono } from "hono";
 import { logger } from "hono/logger";
 import { errorHandler } from "./middleware/index.js";
-import { auth, cards, decks } from "./routes/index.js";
+import { auth, cards, decks, study } from "./routes/index.js";
 
 const app = new Hono();
 
@@ -19,7 +19,8 @@ const routes = app
 	})
 	.route("/api/auth", auth)
 	.route("/api/decks", decks)
-	.route("/api/decks/:deckId/cards", cards);
+	.route("/api/decks/:deckId/cards", cards)
+	.route("/api/decks/:deckId/study", study);
 
 export type AppType = typeof routes;