Refractor/terraform stack cleanup

[Karthikeyannhs]

Description

🧱 api-routing-layer

• Hosts the API Gateway
• Deployed using root credentials for the first time, and then it can be deployed by github actions without effecting the api layer

🧩 api-layer

• Manages Lambda functions and integrations
• Deployed using developer roles
• Mirrors the test environment, where this layer is only deployed by git_hub actions

Context

Type of changes

• Refactoring (non-breaking change)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would change existing functionality)
• Bug fix (non-breaking change which fixes an issue)

Checklist

• I am familiar with the contributing guidelines
• I have followed the code style of the project
• I have added tests to cover my changes
• I have updated the documentation accordingly
• This PR is a result of pair or mob programming

---

Sensitive Information Declaration

To ensure the utmost confidentiality and protect your and others privacy, we kindly ask you to NOT including PII (Personal Identifiable Information) / PID (Personal Identifiable Data) or any other sensitive data in this PR (Pull Request) and the codebase changes. We will remove any PR that do contain any sensitive information. We really appreciate your cooperation in this matter.

• I confirm that neither PII/PID nor sensitive data are included in this PR and the codebase changes.

[Karthikeyannhs]

The API Gateway has been moved to a separate stack(routing-layer) so it can be provisioned using root credentials. Meanwhile, the API Layer continues to be created using developer roles. This mirrors the setup in the test environment, where the API Layer is also deployed using developer roles.