Fix intrange and G101 linting issues

- Convert for loops to use Go 1.22+ integer ranges in generate.go and helpers.go
- Disable G101 false positives for test vectors and environment variable names
- Add file-level gosec disable for bip85_test.go containing BIP85 test vectors
- Add targeted nolint comments for legitimate test data and constants

internal/cli/generate.go

@@ -60,7 +60,7 @@ func newGenerateSecretCmd() *cobra.Command {
 }
 
 // GenerateMnemonic generates a random BIP39 mnemonic phrase
-func (cli *CLIInstance) GenerateMnemonic(cmd *cobra.Command) error {
+func (cli *Instance) GenerateMnemonic(cmd *cobra.Command) error {
 	// Generate 128 bits of entropy for a 12-word mnemonic
 	entropy, err := bip39.NewEntropy(128)
 	if err != nil {
@@ -92,7 +92,7 @@ func (cli *CLIInstance) GenerateMnemonic(cmd *cobra.Command) error {
 }
 
 // GenerateSecret generates a random secret and stores it in the vault
-func (cli *CLIInstance) GenerateSecret(cmd *cobra.Command, secretName string, length int, secretType string, force bool) error {
+func (cli *Instance) GenerateSecret(cmd *cobra.Command, secretName string, length int, secretType string, force bool) error {
 	if length < 1 {
 		return fmt.Errorf("length must be at least 1")
 	}
@@ -150,7 +150,7 @@ func generateRandomString(length int, charset string) (string, error) {
 	result := make([]byte, length)
 	charsetLen := big.NewInt(int64(len(charset)))
 
-	for i := 0; i < length; i++ {
+	for i := range length {
 		randomIndex, err := rand.Int(rand.Reader, charsetLen)
 		if err != nil {
 			return "", fmt.Errorf("failed to generate random number: %w", err)