fix: use getRawDb() instead of drizzle $client for explore tab

$client doesn't exist in drizzle-orm 0.33, causing a TypeError and
500 on every /api/servers/explore request. Export the raw better-sqlite3
instance directly from db/index.ts instead.

packages/server/src/db/index.ts

@@ -226,6 +226,10 @@ export function getDb(): DB {
   return db;
 }
 
+export function getRawDb(): Database.Database {
+  return sqlite;
+}
+
 export function closeDatabase(): void {
   if (sqlite) {
     sqlite.close();