DHCPv6 broken radvd config when switching from static IPv6 address

[Skywalker-11]

Important notices

Before you add a new report, we ask you kindly to acknowledge the following:

• I have read the contributing guide lines at https://github.com/opnsense/core/blob/master/CONTRIBUTING.md
• I am convinced that my issue is new after having checked both open and closed issues at https://github.com/opnsense/core/issues?q=is%3Aissue

Describe the bug

If an interface is configured with static ipv6 configuration and router advertisements is configured (not Disabled) and then the configuration of the interface is switched to DHCPv6 the DHCPv6 solicit requests do not include the configured dhcp options for prefix delegation and address allocation.

To Reproduce

Steps to reproduce the behavior:

1. Configure an interface (usually WAN) with static ipv6 address configuration
2. Configure Router Discovery for that interface to Router only or Managed (probably affects all options except Disable)
3. Apply the configuration
4. Start wireshark or similar to capture DHCPv6 traffic
5. Change the interface to DHCPv6 and configure the DHCPv6 client configuration to send Prefix Delegation and/or Address Allocation
6. Apply the config
7. Check the Wireshark log and see that the DHCPv6 solicit messages do not include fields for Prefix Delegation and/or Address Allocation (which it should)
8. The Router Advertisement options for the configured interface are hidden when DHCPv6 is enabled. To fix that config you have to manually open the URL to the Router Advertisement config page eg. https://your.opnsense.ip:8443/services_router_advertisements.php?if=wan
9. Change the the Router Advertisements option to Disabled. Safe the config.
10. Reapply the interface config
11. Wireshark log shows that the DHCPv6 solicit now contains the Prefix Delegation and/or Address Allocation options (as expected)
12. Reenabling Router Advertisements results in 8) again

Expected behavior

When switching to DHCPv6 on the interface configuration the corresponding Router Advertisement option should be set to Disabled or a warning issued that such a configuration exists and has to be changed. Similar to how a warning is shown if a DHCPv6 server is enabled on that interface when switching to DHCPv6.

Describe alternatives you considered

Alternatively the menu for the Router Advertisement should not be hidden when an interface is configured as DHCPv6 and a textual info always shown that the dhcpv6 options will be ignored if Router Advertisement is enabled for that interface.

Environment

Software version used and hardware type if relevant, e.g.:

OPNsense 24.1.9_4-amd64