LL-HLS : Add need for CDN query args support

[piersoh]

For Low Latency HLS we probably need to add that CDNs need to support passing of query args, potentially back to the origin, to handle the such features as Blocking Playlist Reload, and Playlist Delta Updates when advertised using the Delivery Directives Interface in the EXT-X-SERVER-CONTROL tag.

[technogeek00]

Update 2024/04/24

• Open question: #EXT-X-SERVER-CONTROL indicated CAN-BLOCK-RELOAD is an optional functionality for LL-HLS, but all example and reference implementations use it. Is it truly an optional functionality or practically is it require for LL-HLS to properly operate?
• CDN Pass back of client query arguments something to consider in incremental manifest update text drafting Incremental Manifest Updates #31