- Replace os.MkdirTemp() with t.TempDir() in test files
- Replace os.Setenv() with t.Setenv() in test files
- Remove manual environment cleanup code (t.Setenv automatically restores)
- Remove unused "os" imports from files that no longer use os package
- 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
