feature: add Azure RBAC and Entra ID role assignments to the HCP Terraform service principal

[maor-klir]

Description:

This PR extends the Azure HCP Terraform service principal permissions with additional role assignments required for managing identity and access in common infrastructure provisioning scenarios.

Reasoning:

The original Contributor role is insufficient for common Terraform scenarios where it is required to:

• Create managed identities with role assignments
• Provision Entra ID applications or service principals
• Assign permissions to resources during deployment

These additional permissions follow Azure's principle of least privilege while enabling real-world infrastructure patterns.

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[maor-klir]

Hi @at-wat, @kamatama41, and @mengesb,

I'm tagging you individually for visibility as the team tag (@hashicorp/team-tf-rocket-eng) isn't clickable for me.
This PR is ready for a final review when you have a moment.
Thanks!