Add AWS Secrets Manager connector plugin #184

Feature Description

Add a connector plugin for AWS Secrets Manager so users can securely retrieve secrets and credentials during AWS-centric GRC evidence collection, IaC scanning, and continuous monitoring workflows.

Motivation

AWS-native environments already store secrets in Secrets Manager. A dedicated connector would let the toolkit pull those secrets at runtime instead of requiring users to export them locally, improving both security posture and workflow ergonomics.

Proposed Capabilities

• GetSecretValue with optional version-stage selection (AWSCURRENT, AWSPREVIOUS)
• Read rotation metadata for audit evidence
• Cross-account access via assumed roles
• Integration with aws-inspector and Terraform/CloudFormation scanning workflows
• Region-aware defaulting with override support

Alternatives Considered

• Expect users to aws secretsmanager get-secret-value and export before running (manual, error-prone)
• Use Parameter Store instead (less suited for high-sensitivity credentials)

References

• AWS Secrets Manager docs
• Existing AWS connector pattern: aws-inspector

Linked Linear Issue

Linear: GRC-67