Vaultwarden: add seperate ingress for admin portal

[ksimm1]

Is your feature request related to a problem?

User who enable the admin portal with Vaultwarden will have an insecure vaultwarden.example.com/admin path without specific middleware forcing authentication

Describe the solution you'd like

Add a second ingress for vaultwarden's admin portal on the /admin path. This would allow users to set forward or basic auth middleware just on the admin portal, and leave main ingress as-is.

Describe alternatives you've considered

Current Alternatives

1. manual custom ingress on the /admin path and add forwardauth middleware
2. forwardauth middleware on the main ingress, but have a bypass rule for everything but /admin. steps here for authelia https://truecharts.org/charts/enterprise/authelia/authelia-rules#vaultwarden

Additional context

No response

I've read and agree with the following

• [X] I've checked all open and closed issues and my request is not there.
• [X] I've checked all open and closed pull requests and my request is not there.

[Ornias1993]

If you want to expedite this enhancement, please consider putting a bounty on it here:

https://opencollective.com/truecharts-bounties/contribute/place-bounty-72003