Document new serial port autocomplete field; fix macOS example to use /dev/cu.* not /dev/tty.* Setting-Up-rigctld and CW-Keying-Setup both described the Serial Port / Keyer Serial Port fields as plain manual-entry text fields. Both now auto-populate with serial devices detected on the server machine while staying freely typable. Also corrects the CW Keying Setup macOS example, which listed /dev/tty.* (blocks on DCD) instead of the correct /dev/cu.* dial-out device — the new autocomplete only ever lists cu.* paths.
Fix CW keying Windows splitter guidance, name concrete tools com0com alone (a bare virtual port pair) doesn't bridge to the real physical port both rigctld and the CW keyer need — it needs its bundled hub4com utility, or a purpose-built splitter, to actually relay real-port traffic to multiple virtual endpoints. Replaces the vague "use a virtual COM port pair" guidance with concrete options (com0com+hub4com, VSPE, FabulaTech Serial Port Splitter).
docs: add CW Keying Setup wiki page Step-by-step guide for configuring single-port USB CW keying, covering radio menu settings (IC-7300 detailed), app keyer settings, the Windows single-port limitation, and troubleshooting. Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>