Allow API to set browser, os, device, country, etc.

[blanchardjeremy]

Describe the feature or enhancement

Currently, the following items are set only when a JS request is made from a user's machine to the Umami's servers.

See code here: https://github.com/umami-software/umami/blob/bce70c1034c6668255261c26093a35900b869566/src/lib/session.ts#L39C3-L40C30

const { userAgent, browser, os, ip, country, subdivision1, subdivision2, city, device } =
    await getClientInfo(req);

Many data points can be set via the API directly by POSTing an event: hostname, language, referrer, screen, title, url, website, name, data

Proposed Change

The following items should be something we can set through the API:

• userAgent
• browser
• os
• ip
• country
• device

The appropriate values would need to be documented.

Reason

My use case is that I want to only send server side requests to log page views. This gives me complete control over what data my users expose. And also allows me to make sure their IP address never hits any server other than mine.

As a privacy-focused solution, I think these are in line with your values!

Thanks!