Add module invariants and input validations (#14)

Reviewed-on: deep-stack/laconic2d#14
Co-authored-by: Prathamesh Musale <prathamesh.musale0@gmail.com>
Co-committed-by: Prathamesh Musale <prathamesh.musale0@gmail.com>

x/registry/module/module.go

@@ -27,6 +27,7 @@ var (
 	_ module.HasServices         = AppModule{}
 	_ module.HasConsensusVersion = AppModule{}
 	_ appmodule.HasEndBlocker    = AppModule{}
+	_ module.HasInvariants       = AppModule{}
 )
 
 // ConsensusVersion defines the current module consensus version.
@@ -127,6 +128,12 @@ func (am AppModule) EndBlock(ctx context.Context) error {
 	return EndBlocker(ctx, am.keeper)
 }
 
+// module.HasInvariants
+
+func (am AppModule) RegisterInvariants(ir sdk.InvariantRegistry) {
+	keeper.RegisterInvariants(ir, am.keeper)
+}
+
 // Get the root tx command of this module
 func (AppModule) GetTxCmd() *cobra.Command {
 	return cli.GetTxCmd()