feat: support to build FTS without positions (#1621)

nodejs/src/index.rs

@@ -92,9 +92,13 @@ impl Index {
     }
 
     #[napi(factory)]
-    pub fn fts() -> Self {
+    pub fn fts(with_position: Option<bool>) -> Self {
+        let mut opts = FtsIndexBuilder::default();
+        if let Some(with_position) = with_position {
+            opts = opts.with_position(with_position);
+        }
         Self {
-            inner: Mutex::new(Some(LanceDbIndex::FTS(FtsIndexBuilder::default()))),
+            inner: Mutex::new(Some(LanceDbIndex::FTS(opts))),
         }
     }
 }