desktop修正

backend/app/core/fiscal_lock.py

@@ -0,0 +1,19 @@
+from fastapi import HTTPException
+from app.core.database import get_connection
+
+def check_fiscal_year_unlocked(journal_date):
+    fiscal_year = journal_date.year
+
+    with get_connection() as conn, conn.cursor() as cur:
+        cur.execute("""
+            SELECT is_locked
+              FROM fiscal_year_locks
+             WHERE fiscal_year = %s
+        """, (fiscal_year,))
+        row = cur.fetchone()
+
+        if row and row["is_locked"]:
+            raise HTTPException(
+                status_code=400,
+                detail="この会計年度は既に確定されているため、仕訳を変更できません。"
+            )