c/a/api: reorganize and add AgentInit

Move hardware reporting-related data into a separate file for better
organization.

Also add an AgentInit message which will be used to pass data to the
Agent.

Change-Id: I1eecbd5a78da03170651f76f9f24e134dddaca4f
Reviewed-on: https://review.monogon.dev/c/monogon/+/1140
Reviewed-by: Leopold Schabel <leo@monogon.tech>
Tested-by: Leopold Schabel <leo@monogon.tech>
diff --git a/cloud/shepherd/equinix/manager/test_agent/main.go b/cloud/shepherd/equinix/manager/test_agent/main.go
index 5dd5ccd..8f29c30 100644
--- a/cloud/shepherd/equinix/manager/test_agent/main.go
+++ b/cloud/shepherd/equinix/manager/test_agent/main.go
@@ -36,8 +36,10 @@
 		return
 	}
 	arsp := apb.TakeoverResponse{
-		InitMessage: &aim,
-		Key:         pub,
+		Result: &apb.TakeoverResponse_Success{Success: &apb.TakeoverSuccess{
+			InitMessage: &aim,
+			Key:         pub,
+		}},
 	}
 	arspb, err := proto.Marshal(&arsp)
 	if err != nil {