Config accepts structured host/port/channel/username/password (or the
existing rtsp_url_env) and builds the RTSP URL with RFC 3986 percent-
encoded credentials, so passwords containing @/:/ no longer break parsing.
Credentials are excluded from config_version; a guard test keeps the
public example credential-free. probe_stream does a bounded connection
test. 59 tests pass.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
