- Implement Secure .env masking using conceal with WarningMsg highlight.
- Cache environment lines on buffer load to restore original values.
- Add <leader>et keymap to toggle masking per buffer.
- Preserve masked content across BufWriteCmd by re‑injecting cached lines.
Enhancements:
- Replace ad‑hoc masking with a dedicated `secure_env` namespace.
- Expand autocmd events to include BufWriteCmd for write‑preserve behavior.
- Use proper namespace handling and deepcopy to avoid side effects.
Bug Fixes:
- Remove stale toggle that caused UI flicker and confusion.
- Ensure write operations succeed when masked content remains unchanged.
sankalp
8b1603ced7