fix: make the store.proto match the RFC definition

waku/store/v2beta4/store.proto

@@ -14,13 +14,13 @@ message Index {
 }
 
 message PagingInfo {
-  optional uint64 page_size = 1;
-  optional Index cursor = 2;
+  uint64 page_size = 1;
+  Index cursor = 2;
   enum Direction {
     BACKWARD = 0;
     FORWARD = 1;
   }
-  optional Direction direction = 3;
+  Direction direction = 3;
 }
 
 message ContentFilter {
@@ -29,17 +29,17 @@ message ContentFilter {
 
 message HistoryQuery {
   // The first field is reserved for future use
-  optional string pubsub_topic = 2;
+  string pubsub_topic = 2;
   repeated ContentFilter content_filters = 3;
-  optional PagingInfo paging_info = 4;
+  PagingInfo paging_info = 4;
   optional sint64 start_time = 5;
   optional sint64 end_time = 6;
 }
 
 message HistoryResponse {
-  // The first field is reserved for future use
+  // the first field is reserved for future use
   repeated waku.message.v1.WakuMessage messages = 2;
-  optional PagingInfo paging_info = 3;
+  PagingInfo paging_info = 3;
   enum Error {
     NONE = 0;
     INVALID_CURSOR = 1;
@@ -49,6 +49,6 @@ message HistoryResponse {
 
 message HistoryRPC {
   string request_id = 1;
-  optional HistoryQuery query = 2;
-  optional HistoryResponse response = 3;
+  HistoryQuery query = 2;
+  HistoryResponse response = 3;
 }