switch to using the timestamp time instead of a string

Cargo.lock

@@ -740,7 +740,7 @@ checksum = "0bf256ce5efdfa370213c1dabab5935a12e49f2c58d15e9eac2870d3b4f27263"
 
 [[package]]
 name = "tap-interface"
-version = "0.2.0"
+version = "1.0.0"
 dependencies = [
  "prost",
  "prost-types",

Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "tap-interface"
-version = "0.2.0"
+version = "1.0.0"
 edition = "2024"
 description = "Protobuf definitions for TAP"
 authors = ["Joey Hines joey@ahines.net"]

src/service.proto

@@ -1,5 +1,7 @@
 syntax = "proto3";
 
+import "google/protobuf/timestamp.proto";
+
 package tap.service;
 
 message SessionKeyReq {
@@ -9,7 +11,7 @@ message SessionKeyReq {
 message SessionKeyResp {
   uint64 user_id  = 1;
   bytes session_key = 2;
-  string expiration_time = 3;
+  google.protobuf.Timestamp expiration_time = 3;
 }
 
 service TAP {