batch API requests are ignored if User-Agent is empty

[astappiev]

Describe the Bug

After the introduction of batch event submission, I wanted to try it inside https://github.com/astappiev/traefik-umami-plugin
But unfortunately, I met an error that blocked me from further processing.

I received seems-to-be expected response {"size":1,"processed":1,"errors":0,"details":[]}, however no events were added.
After a few hours spent trying different approaches, I submitted the same payload via send method and realized that it's simply {beep: 'boop'}.

So, yes, my client's user-agent is empty, and it bounces immediately at the beginning of the send processing, despite that I use userAgent as a property of event's payload.

Things that would be nice to address:

• The requester User-Agent header is empty, but userAgent is provided inside the request body.
• I still would like individual events to be checked for bots and ignored if so.
• Maybe improve batch output, e.g. return number of ignored events.

Database

PostgreSQL

Relevant log output

Which Umami version are you using? (if relevant)

2.17.0

Which browser are you using? (if relevant)

No response

How are you deploying your application? (if relevant)

No response