error message is confusing for the example on the treadme.md

[rahul1990gupta]

Thanks for putting this extension together.

As I was going through the readme page of the extension. I noticed that it was working with 'k= ?', but not with the limit. That should be okay. But the message was saying that either of them will do in a query. So,

• either we change the message
• support limit and k both.

sqlite> select rowid, distance from vec_examples where sample_embedding match '[0.890, 0.544, 0.825, 0.961, 0.358, 0.0196, 0.521, 0.175]' and k=1;
2|2.38687372207642
sqlite> 
sqlite> 
sqlite> 
sqlite> select rowid, distance from vec_examples where sample_embedding match '[0.890, 0.544, 0.825, 0.961, 0.358, 0.0196, 0.521, 0.175]' limit 2 ;
Error: in prepare, A LIMIT or 'k = ?' constraint is required on vec0 knn queries. (1)