ci(node): check docs in CI (#2084)

* Make `npm run docs` fail if there are any warnings. This will catch
items missing from the API reference.
* Add a check in our CI to make sure `npm run dos` runs without warnings
and doesn't generate any new files (indicating it might be out-of-date.
* Hide constructors that aren't user facing.
* Remove unused enum `WriteMode`.

Closes #2068

nodejs/typedoc.json

@@ -1,11 +1,9 @@
 {
   "intentionallyNotExported": [
-    "lancedb/native.d.ts:Connection",
-    "lancedb/native.d.ts:Index",
     "lancedb/native.d.ts:Query",
     "lancedb/native.d.ts:VectorQuery",
     "lancedb/native.d.ts:RecordBatchIterator",
-    "lancedb/native.d.ts:Table"
+    "lancedb/native.d.ts:NativeMergeInsertBuilder"
   ],
   "useHTMLEncodedBrackets": true,
   "useCodeBlocks": true,