Rename netutils, jconf, stream, aead, aead2022, aead2022_udp, crypto,
acl, plugin, plugin_disabled and resolv from .c to .cpp without changing
their contents, and update source lists, snippet references, test
comments and debian/copyright.
The Doxygen source list and scripts/check_cli_docs.py now accept either
extension for each module, so the remaining programs can move one at a
time. The new .cpp files are added to the no-heap ratchet baseline.
Interactive whiptail/dialog TUI for server/client config generation,
systemd service management, SIP003 plugin installation, and ss:// URI
output. Includes 131 bash unit tests covering all utility functions
(validation, JSON generation, URI encoding, config round-trip parsing).
Tests run in CTest and as a dedicated GitHub Actions step.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>