[Feature Request] Extend gemini-enterprise blueprint to support FedRAMP Moderate

## Feature Description
Update Gemini Enterprise deployment blueprint to comply with FedRAMP Moderate requirements.

## Use Case
Allows customers to deploy Gemini for Government to comply with FedRAMP Moderate requirements.

## Proposed Solution
A Pull Request containing all required functionality for the FedRAMP Moderate compliance regime support for Gemini Enterprise.

This includes updates to the Terraform resources as well as the `deploy.sh` script to support this new regime.

## Compliance & Deployment Context
* **Target Deployment Type(s):**
* [ ] US Region Restricted (e.g., Access Policy constraint)
* [x] FedRAMP Moderate
* [ ] FedRAMP High
* [ ] DoD IL4
* [ ] DoD IL5
* [ ] All / General
* **Relevant NIST 800-53r5 Controls:** (If applicable, list the controls this feature helps satisfy)

## Reusability Check
Stellar Engine prioritizes reusability.
* [x] I have checked if this functionality can be achieved by extending an existing module or blueprint.
* [x] I have verified that this does not duplicate existing functionality.