Pass media metadata to external m3u8 players

Describe your suggested feature

I've been working on an helper app, that can intercept intent from "Play in m3u8 player" button to send the m3u8 file to a device running an express server, effectively playing it.

But currently cloudstream does not include any metadata about the media in this m3u8 file. So I have to extract it using the content-disposition headers from the links.

It would be nice to have this as native HLS metadata, as other m3u8 players would also be able to display the title properly.

for example:

#EXTM3U
#EXT-X-VERSION:3
#EXT-X-TARGETDURATION:10

# Metadata attached directly to the track/stream line
#EXTINF:10.0 title="The Matrix" year="1999" genre="Sci-Fi",The Matrix (1999)
segment1.ts

or

#EXTM3U
#EXT-X-VERSION:7

# Global Metadata using Session Data (Requires V7+)
#EXT-X-SESSION-DATA:DATA-ID="com.lagradost.cloudstream3.title",VALUE="The Matrix"
#EXT-X-SESSION-DATA:DATA-ID="com.lagradost.cloudstream3.year",VALUE="1999"
#EXT-X-SESSION-DATA:DATA-ID="com.lagradost.cloudstream3.genre",VALUE="Sci-Fi" 

#EXT-X-TARGETDURATION:10
#EXTINF:10.0,
segment1.ts

https://github.com/user-attachments/assets/b8cffdff-ad31-469b-afce-169a0e9d89dc

Other details

No response

Acknowledgements

• My suggestion is NOT about adding a new provider
• I have searched the existing issues and this is a new ticket, NOT a duplicate or related to another open issue.

Start at the code behind the “Play in m3u8 player” button and locate where the HLS playlist is assembled. Compare the proposed track and session metadata approaches, then verify that an external m3u8 player receives and displays the media title and related metadata.