Support / add `proxy-server` input mode to fuzz / run checks on live traffic

[tarunKoyalwar]

Please describe your feature request:

• follow-up of https://github.com/projectdiscovery/nuclei/pull/4941#pullrequestreview-1961321544
• the idea is to add / implement a proxy server in nuclei ( more like proxify + nuclei ) integration to run templates / checks on live proxy traffic

Describe the use case of this feature:

• this will eliminate format specific dependencies & edgecase handling like we do in openapi schema etc

Know Issues

• Fuzzing Live traffic actively might not be as helpful since it has its own set of challenges like unresponsiveness in browser , ratelimits hit due to sending large number of requests etc

[Mzack9999]

I think it's way more functional than blind DAST fuzzing as, for example, it allows specific authorization checks like https://github.com/PortSwigger/autorize, that are the most difficult to catch and generally the most impactful ones