feat(tci): key CW through the radio's own macro keyer

The sixth CW engine, and the one the TCI backend was left without. A SunSDR
keys from the WebSocket that already carries the CAT: no WinKeyer, no second
serial port, nothing to wire.

    CW_MACROS:0,<text>;     send
    CW_MACROS_SPEED:<wpm>;  speed
    CW_MACROS_STOP;         abort

Confirmed against the TCI command table in ars-ka0s/eesdr-tci — the source that
settled SPOT. CW_MACROS rather than TCI 2.0's CW_MSG: it exists from 1.6, and
OpsLog resolves its own variables, so the before/after callsign fields have
nothing to carry.

Commas and semicolons are stripped before sending. They are the protocol's own
separators: a comma would become another argument, a semicolon would end the
command with the message half keyed and the rest parsed as a command.

Only the MACRO speed is set, not the paddle keyer's — an operator who set their
paddle to 28 wpm did not ask for it to change because a macro went out at 25.
And there is no backspace: TCI can stop a message but cannot un-type one, so the
type-ahead correction the Flex engine offers is absent rather than faked.

frontend/wailsjs/go/main/App.d.ts

@@ -1279,6 +1279,12 @@ export function SyncFolderNow():Promise<number>;
 
 export function SyncPOTAHunterLog(arg1:boolean,arg2:boolean):Promise<main.POTASyncResult>;
 
+export function TCISendCW(arg1:string):Promise<void>;
+
+export function TCISetKeySpeed(arg1:number):Promise<void>;
+
+export function TCIStopCW():Promise<void>;
+
 export function TailLogFile(arg1:number):Promise<string>;
 
 export function TestCloudlogUpload():Promise<string>;