feat(server): in-place testnet creator

CHANGELOG.md

@@ -52,6 +52,7 @@ Every module contains its own CHANGELOG.md. Please refer to the module you are i
 * (baseapp) [#18499](https://github.com/cosmos/cosmos-sdk/pull/18499) Add `MsgRouter` response type from message name function.
 * (types) [#18768](https://github.com/cosmos/cosmos-sdk/pull/18768) Add MustValAddressFromBech32 function.
 * (gRPC) [#19049](https://github.com/cosmos/cosmos-sdk/pull/19049) Add debug log prints for each gRPC request.
+* (server) [#19280](https://github.com/cosmos/cosmos-sdk/pull/19280) Adds in-place testnet CLI command.
 
 ### Improvements
 

baseapp/options.go

@@ -107,6 +107,11 @@ func SetChainID(chainID string) func(*BaseApp) {
 	return func(app *BaseApp) { app.chainID = chainID }
 }
 
+// SetStoreLoader allows customization of the rootMultiStore initialization.
+func SetStoreLoader(loader StoreLoader) func(*BaseApp) {
+	return func(app *BaseApp) { app.SetStoreLoader(loader) }
+}
+
 // SetOptimisticExecution enables optimistic execution.
 func SetOptimisticExecution(opts ...func(*oe.OptimisticExecution)) func(*BaseApp) {
 	return func(app *BaseApp) {