[FEAT] Handle all `up` flags as role variables

[Ari Kalfus]

We're up to 3 or so exceptions to tailscale_args, where some flags are handled by dedicated variables in this role and most are not. This is confusing behavior. Originally, tailscale_args was set up this way because the Tailscale CLI was new and undergoing rapid development and there wasn't a guarantee that flags would be stable. This is no longer the case, and supporting all flags as arguments to this role would simplify usage and "Ansible-ize" the rest of the parameters.