refactor: extract SQLite connection configuration to reduce duplication

Extracted _configure_sqlite_connection() function to eliminate duplicate
code in _create_engine_and_session() and engine_session_factory().

This DRY refactoring makes the WAL mode and PRAGMA configuration easier
to maintain and test.

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

Co-Authored-By: Claude <noreply@anthropic.com>
Signed-off-by: phernandez <paul@basicmachines.co>

Author: phernandez

src/basic_memory/db.py

@@ -75,6 +75,23 @@ async def scoped_session(
         await factory.remove()
 
 
+def _configure_sqlite_connection(dbapi_conn) -> None:
+    """Configure SQLite connection with WAL mode and optimizations."""
+    cursor = dbapi_conn.cursor()
+    # Enable WAL mode for better concurrency
+    cursor.execute("PRAGMA journal_mode=WAL")
+    # Set busy timeout to handle locked databases
+    cursor.execute("PRAGMA busy_timeout=10000")  # 10 seconds
+    # Optimize for performance
+    cursor.execute("PRAGMA synchronous=NORMAL")
+    cursor.execute("PRAGMA cache_size=-64000")  # 64MB cache
+    cursor.execute("PRAGMA temp_store=MEMORY")
+    # Windows-specific optimizations
+    if os.name == "nt":
+        cursor.execute("PRAGMA locking_mode=NORMAL")  # Ensure normal locking on Windows
+    cursor.close()
+
+
 def _create_engine_and_session(
     db_path: Path, db_type: DatabaseType = DatabaseType.FILESYSTEM
 ) -> tuple[AsyncEngine, async_sessionmaker[AsyncSession]]:
@@ -107,19 +124,7 @@ def _create_engine_and_session(
     @event.listens_for(engine.sync_engine, "connect")
     def enable_wal_mode(dbapi_conn, connection_record):
         """Enable WAL mode on each connection."""
-        cursor = dbapi_conn.cursor()
-        # Enable WAL mode for better concurrency
-        cursor.execute("PRAGMA journal_mode=WAL")
-        # Set busy timeout to handle locked databases
-        cursor.execute("PRAGMA busy_timeout=10000")  # 10 seconds
-        # Optimize for performance
-        cursor.execute("PRAGMA synchronous=NORMAL")
-        cursor.execute("PRAGMA cache_size=-64000")  # 64MB cache
-        cursor.execute("PRAGMA temp_store=MEMORY")
-        # Windows-specific optimizations
-        if os.name == "nt":
-            cursor.execute("PRAGMA locking_mode=NORMAL")  # Ensure normal locking on Windows
-        cursor.close()
+        _configure_sqlite_connection(dbapi_conn)
 
     session_maker = async_sessionmaker(engine, expire_on_commit=False)
     return engine, session_maker
@@ -206,19 +211,7 @@ async def engine_session_factory(
     @event.listens_for(_engine.sync_engine, "connect")
     def enable_wal_mode(dbapi_conn, connection_record):
         """Enable WAL mode on each connection."""
-        cursor = dbapi_conn.cursor()
-        # Enable WAL mode for better concurrency
-        cursor.execute("PRAGMA journal_mode=WAL")
-        # Set busy timeout to handle locked databases
-        cursor.execute("PRAGMA busy_timeout=10000")  # 10 seconds
-        # Optimize for performance
-        cursor.execute("PRAGMA synchronous=NORMAL")
-        cursor.execute("PRAGMA cache_size=-64000")  # 64MB cache
-        cursor.execute("PRAGMA temp_store=MEMORY")
-        # Windows-specific optimizations
-        if os.name == "nt":
-            cursor.execute("PRAGMA locking_mode=NORMAL")  # Ensure normal locking on Windows
-        cursor.close()
+        _configure_sqlite_connection(dbapi_conn)
 
     try:
         _session_maker = async_sessionmaker(_engine, expire_on_commit=False)