feat: add ddl task service (#53)

* feat: add ddl task service

* chore: apply suggestions from CR

* chore: add path to build.rs

proto/greptime/v1/meta/route.proto

@@ -21,8 +21,6 @@ option go_package = "github.com/GreptimeTeam/greptime-proto/go/greptime/v1/meta"
 import "greptime/v1/meta/common.proto";
 
 service Router {
-  rpc Create(CreateRequest) returns (RouteResponse) {}
-
   // Fetch routing information for tables. The smallest unit is the complete
   // routing information(all regions) of a table.
   //
@@ -47,14 +45,6 @@ service Router {
   rpc Delete(DeleteRequest) returns (RouteResponse) {}
 }
 
-message CreateRequest {
-  RequestHeader header = 1;
-
-  TableName table_name = 2;
-  repeated Partition partitions = 3;
-  bytes table_info = 4;
-}
-
 message RouteRequest {
   RequestHeader header = 1;