🙏 Sponsor should be a required input when creating Agent Identity Blueprints and Agent Identities to mirror the APIs and New-* cmdlets should suggest signed-in User like the wizard does

[jesakowi]

Describe the feature

The MS Graph APIs for creating an AIB and Agent Identity both require at least one Sponsor specified at create time. The cmdlets treat this as an optional input today, but these should be required.

The standalone New-* cmdlets for all three entities (including AIBP) should also offer to use the signed in user as Sponsor, like the Invoke cmdlet does.

How will this feature enhance your project and further the project’s overall goals? Who will benefit from this feature (i.e. all users; the project team)?
Requiring these upfront will help the user avoid a late bound failure for the Invoke wizard and the New-* cmdlets for these entities. Offering to use the signed-in user as Sponsor will also simplify in cases where this person is the correct (and only) Sponsor.

Describe alternatives you've considered
N/A

Additional context

N/A