NOISSUE - Fetch attestation report (#66)

* Improve attestation and update deps

Enhanced the attestation process to require additional report data and a variable privacy level, catering to varying security requirements. The `Run` method's context parameter was removed to simplify invocation following API alignment. Dependencies got updated, notably adding `github.com/google/go-sev-guest` for attestation, and some were indirectly bumped. These updates ensure the agent service leverages the latest available features and improvements for security and stability.

Signed-off-by: SammyOina <sammyoina@gmail.com>

* Extend AttestationRequest with data fields

Enhanced the AttestationRequest message structure by introducing 'report_data' and 'vpml' fields to encapsulate additional attestation context. Adjusted service and middleware layers to incorporate these new parameters, enabling richer attestation workflows. The GRPC endpoint, logging, and metrics layers have been updated to handle the additional data, catering to more secure and nuanced attestation use cases.

Refactors Attestation command in CLI to accept report data argument and include an optional 'vpml' flag for specifying virtual machine privilege level. This change empowers users to request attestation with specific context directly from the CLI.

Signed-off-by: SammyOina <sammyoina@gmail.com>

* Refactor attestation to remove vpml dependency

Removed the `vpml` field from the AttestationRequest protobuf, and all associated handling code, streamlining the attestation process. Code adjustments were made in gRPC client, server, and service layers to ensure proper request construction and validation that focuses only on report data. This change simplifies the attestation API and its usage, reducing error risk and improving maintainability. It reflects a decision to decouple the protocol from specific vendor measurement levels, potentially due to a shift towards a more generalized attestation procedure.

Signed-off-by: SammyOina <sammyoina@gmail.com>

* Enhance CLI usability and streamline SDK attestation

- Added a usage example to the CLI attestation command for better user guidance.
- Simplified the SDK attestation function by removing an unused parameter and directly populating the request structure with report data to align function parameters with actual usage requirements.

Signed-off-by: SammyOina <sammyoina@gmail.com>

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Signed-off-by: SammyOina <sammyoina@gmail.com>

cmd/agent/main.go

@@ -66,7 +66,7 @@ func main() {
 	defer eventSvc.Close()
 	svc := newService(ctx, logger, eventSvc)
 
-	if _, err := svc.Run(ctx, cfg); err != nil {
+	if _, err := svc.Run(cfg); err != nil {
 		if err := eventSvc.SendEvent("init", "failed", json.RawMessage{}); err != nil {
 			logger.Warn(err.Error())
 		}