Block changing VPN network in Location when there are devices available

[kchudy]

• This might cause conflicts if admin assigned static IPs.
• Add to documentation: all actions that cause the static IPs to get reset (adding/removing users from groups, disabling a user, adding/removing groups from locations).

[kchudy]

@Va1ter Please provide design example for blocking input edit with a warning.

[Va1ter]

@kchudy https://www.figma.com/design/dZgIk8Ph3EXT0pGfH51MAW/Core?node-id=3615-32476&t=n96mohf4LLsm7Lc9-11