accounts, cmd, internal, signer: add note about backing up the keystore (#19432)

* accounts: add note about backing up the keystore

* cmd, accounts: move the printout to accountCreate

* internal, signer: add info when new account is created via rpc

* cmd, internal, signer: split logs

* cmd/geth: make account new output a bit more verbose

internal/ethapi/api.go

@@ -295,6 +295,9 @@ func (s *PrivateAccountAPI) DeriveAccount(url string, path string, pin *bool) (a
 func (s *PrivateAccountAPI) NewAccount(password string) (common.Address, error) {
 	acc, err := fetchKeystore(s.am).NewAccount(password)
 	if err == nil {
+		log.Info("Your new key was generated", "address", acc.Address)
+		log.Warn("Please backup your key file!", "path", acc.URL.Path)
+		log.Warn("Please remember your password!")
 		return acc.Address, nil
 	}
 	return common.Address{}, err