Add GetServiceVersion for both client and exporter

Author: mangelajo

proto/jumpstarter/client/v1/client.proto

@@ -56,6 +56,11 @@ service ClientService {
     option (google.api.http) = {delete: "/v1/{name=namespaces/*/leases/*}"};
     option (google.api.method_signature) = "name";
   }
+
+  rpc GetServiceVersion(google.protobuf.Empty) returns (GetServiceVersionResponse) {
+    option (google.api.http) = {get: "/v1/version"};
+    option (google.api.method_signature) = "";
+  }
 }
 
 message Exporter {
@@ -168,3 +173,9 @@ message DeleteLeaseRequest {
     (google.api.resource_reference) = {type: "jumpstarter.dev/Lease"}
   ];
 }
+
+message GetServiceVersionResponse {
+  string version = 1 [(google.api.field_behavior) = OUTPUT_ONLY];
+  string build_date = 2 [(google.api.field_behavior) = OUTPUT_ONLY];
+  string git_commit = 3 [(google.api.field_behavior) = OUTPUT_ONLY];
+}

proto/jumpstarter/v1/jumpstarter.proto

@@ -13,6 +13,7 @@ import "jumpstarter/v1/common.proto";
 
 // A service where a exporter can connect to make itself available
 service ControllerService {
+  rpc GetServiceVersion(google.protobuf.Empty) returns (GetServiceVersionResponse);
   // Exporter registration
   rpc Register(RegisterRequest) returns (RegisterResponse);
 
@@ -228,3 +229,9 @@ message GetStatusResponse {
   ExporterStatus status = 1;
   optional string message = 2;
 }
+
+message GetServiceVersionResponse {
+  string version = 1;
+  string build_date = 2;
+  string git_commit = 3;
+}