Adds policy keys ExitNodeID and ExitNodeIP. Uses the policy keys to determine the exit node in preferences. Fixes tailscale/corp#15683 Signed-off-by: Claire Wang <claire@tailscale.com>
Add a more generalized package for getting policies. Updates tailcale/corp#10967 Signed-off-by: Claire Wang <claire@tailscale.com> Co-authored-by: Adrian Dewhurst <adrian@tailscale.com>