[Feature]: Support for multi-proxy config via Playwright

Feature Request

Currently, the only way to use a proxy is through test options in proxy. This works fine for most cases, but there is sometimes a need for a more granular approach to control request distribution based on certain rules or controlled randomization of source to the target.

Example

Example Scenarios -

• User should be able to set authenticated proxy config per session - Already supported
• User should be able to configure domain-based proxy - helps in routing traffic to different proxies for different domains (might also help in geographical distribution based on domain)
• Should be able to configure proxy settings to deny/allow domains - Included domains in proxy config are allowed while rest are denied by default
• Should be able to provide set of proxies and enable proxy rotation - helps in randomizing source for the same target.

Motivation

Most of these capabilities could be achieved with the help of PAC files as well, similar to the description in an issue here.

It will make playwright better by allowing more specific tests to be performed depending on proxy. More flexibility in proxy allows developers to easily connect to resources required for testing.