[🚀 Feature]: [dotnet] Support Activity monitoring

### Description

https://learn.microsoft.com/en-us/dotnet/api/system.diagnostics.activitysource?view=net-11.0-pp

Low-level libraries like Selenium are able to emit information about commands/events. Selenium can support it for free, "one line" code.

### Motivation
When I started to contribute, I continuosly was creating "helper projects" to see how fast Selenium is. We can do it built in easily.

### Implementation
- Easy
- No extra dependencies
- Need to decide what we want to emit as "events"
- No performance penalty

### Example
I successfully introduced it in https://github.com/nvborisenko/selenium.webdriver.bidi.cdp

### Have you considered any alternatives or workarounds?

Currently only via internal logging.

Start with the linked System.Diagnostics.ActivitySource documentation and Selenium's existing internal logging paths; the issue does not name specific files or tests. Determine which command/event signals should be emitted and how the result can be checked without adding dependencies or a performance penalty.

Written by the indexing model from the issue text.