Remove new dashboard

[zarik5]

Revert settings-schema to old version

[xytovl]

Fails to build for me thread 'main' panicked at 'called Result::unwrap()on anErr value: Error { kind: NotFound, message: "No such file or directory (os error 2)" }', alvr/xtask/src/main.rs:232:89

    let dir_content =
        dirx::get_dir_content2("alvr/legacy_dashboard", &dirx::DirOptions { depth: 1 }).unwrap();
    let items: Vec<&String> = dir_content.directories[1..]
        .iter()
        .chain(dir_content.files.iter())
        .collect();

[zarik5]

I corrected it before but I forgot to do it again in the merge commit.

[xytovl]

builds and launches fine, I didn't go through all the changes but seems all fine