Blocklist feature no longer works with SteamLinuxRuntime 1.0

Context

Describe the background for the issue/task.

Steam is now enable slr(steamlinuxruntime) 1.0 for all Linux Native Games by default in steam beta release. this broke steam flatpak ability to block specific libraries as workaround for native linux games like libtcmalloc issue on source engine games.

This is important for multiplayer source engine games since VAC apparently didn't like proton so it will run in insecure mode.

Description

Describe the implementation plan. A check list should be used.

There is launch option -compat-force-slr off for disabling steamlinuxruntime 1.0 by default on all native linux games.

Acceptance Criteria

Identify how this is to be 'proven'. Use links here to the MR, to the documentation, to the demo location, whatever it is that is that is being delivered.

You can test this by opt in into steam beta update and try to run games from this list steam flathub blocklist