docs: simplify loadtest mode generation instructions

Author: minhd-vu

CLAUDE.md

@@ -96,7 +96,7 @@ When adding a new command:
 2. Add the command to `cmd/root.go` in the `NewPolycliCommand()` function
 3. Create a usage documentation file (e.g., `yourCommandUsage.md`)
 4. Run `make gen-doc` to update the main documentation
-5. If adding a new loadtest mode, run `make gen-load-test-modes` after using stringer
+5. If adding a new loadtest mode, run `make gen-load-test-modes`
 
 ## CI/CD Considerations
 

README.md

@@ -203,4 +203,4 @@ websocat ws://34.208.176.205:9944
 {"jsonrpc":"2.0", "id": 1, "method": "chain_subscribeNewHead", "params": []}
 ```
 
-If you add a new loadtest mode, don't forget to update the loadtest mode string by running the following command: `cd cmd/loadtest && stringer -type=loadTestMode`. You can install [stringer](https://pkg.go.dev/golang.org/x/tools/cmd/stringer) with `go install golang.org/x/tools/cmd/stringer@v0.37.0`.
+If you add a new loadtest mode, don't forget to update the loadtest mode string by running `make gen-load-test-modes`.