Add missing fields from the API

[lmagyar]

Proposed Changes

Adds missing fields from the API:

• not optional
  • clientConnectivity/latency
  • connected_to_control (supersedes #1233)
  • node_id (supersedes #1187, preserves author, makes field non-optional)
  • tailnet_lock_key
• optional (because these are not always present)
  • isEphemeral
  • multiple_connections
  • ssh_enabled
  • tailnet_lock_error (empty string converted to None)

Tested on the real API.

Not implemented fields:

• postureIdentity (This field is available for Enterprise plans.)

Related Issues

[lmagyar]

Added latency also.

[lmagyar]

Fixed some typos.