Add support for both Qtip and UDP traffic for Server Listeners.

[ProjectsByJackHe]

Description

Currently, we have an execution parameter (QUIC_EXECUTION_CONFIG_FLAG_QTIP) that you set to either process packets via QTIP or normal QUIC/UDP traffic.

For a server listener, that means you can only talk to clients with the same execution profile as you; you either deal over QTIP or QUIC/UDP.

This is inconvenient and sometimes a blocker when you want your listener to accept from clients with varying execution parameters (QTIP through the Azure load balancer, normal QUIC/UDP for on-prem clients)

Changes
The main behavior change is that now all Server listeners created will accept both QTIP and QUIC+udp traffic by default when XDP is configured and running correctly.

To support this new design and make testing a bit easier, we also add a knob (QUIC_SETTINGS) to control whether a connection created / listener created is going to send QUIC+udp/QTIP.

This pull-request also updates the behavior of QUIC_EXECUTION_CONFIG_FLAG_QTIP: If you set this flag, all client connections created will default to using QTIP unless otherwise specified. Note that the QUIC_EXECUTION_CONFIG_FLAG_QTIP does not impact server Listeners as they will always accept both QUIC/QTIP traffic assuming XDP is configured and running correctly.

This PR adds an API (connection Get/Set parameter) for client connections to specify whether the connection sends normal QUIC and/or TCP traffic.

Closes: #3516

Testing

Added a datatest to alternate between creating normal QUIC connections and QTIP connections, where they all ping the same listener.

Documentation

QTIPEnabled in QUIC_SETTINGS will be documented.

[codecov]

Codecov Report

Attention: Patch coverage is 73.52941% with 9 lines in your changes missing coverage. Please review.

Project coverage is 87.23%. Comparing base (abf74b1) to head (a6a9c2e).
Report is 1 commits behind head on main.

Files with missing lines	Patch %	Lines
src/core/connection.c	57.14%	3 Missing ⚠️
src/core/settings.c	82.35%	3 Missing ⚠️
src/core/connection_pool.c	66.66%	2 Missing ⚠️
src/core/listener.c	50.00%	1 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #4803      +/-   ##
==========================================
+ Coverage   84.98%   87.23%   +2.25%     
==========================================
  Files          57       57              
  Lines       17952    17982      +30     
==========================================
+ Hits        15256    15687     +431     
+ Misses       2696     2295     -401     

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