feat(station): drive the motorized antenna from its widget

It showed pattern, elements and Retract — everything except where the antenna
is pointed, which is the thing an operator changes most. Tuning it meant opening
Settings or moving the rig.

A button per band, taken from the bands configured in Settings rather than a
list invented here: a band dropped there cannot be clicked here. They point at
where people actually work, not the arithmetic centre — 20 m centres on 14175
and nobody lives there, 10 m spans 1.7 MHz of which the top half is empty.

Up and down move 25 kHz, which is also the finest tracking threshold: a smaller
nudge would be undone by the next poll while tracking is on. They work from the
ANTENNA's frequency, not the rig's, or walking the antenna across a band while
the rig stays put would be undone on the first press.

Tracking moved within reach because it is an operating decision — off to park
the antenna, on to resume — not something set up once. Its step only appears
when it is on: a threshold for something switched off is a question the operator
cannot act on.

MotorTuneKHz carries the CURRENT direction rather than resetting it. Both
controllers set frequency and pattern in one command, so a bare frequency would
silently drop a 180° or bidirectional pattern — a beam turning round is not an
acceptable side effect of clicking a band.

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

@@ -682,10 +682,14 @@ export function LookupCallsign(arg1:string):Promise<lookup.Result>;
 
 export function LookupCallsignFresh(arg1:string):Promise<lookup.Result>;
 
+export function MotorNudgeKHz(arg1:number):Promise<void>;
+
 export function MotorReadElements():Promise<Array<number>>;
 
 export function MotorSetElement(arg1:number,arg2:number):Promise<void>;
 
+export function MotorTuneKHz(arg1:number):Promise<void>;
+
 export function MoveDatabase(arg1:string):Promise<void>;
 
 export function NetActivate(arg1:string):Promise<qso.QSO>;
@@ -976,6 +980,8 @@ export function SetDVKLabel(arg1:number,arg2:string):Promise<void>;
 
 export function SetKenwoodKeySpeed(arg1:number):Promise<void>;
 
+export function SetMotorFollow(arg1:boolean,arg2:number):Promise<void>;
+
 export function SetOpsLogQSLReceived(arg1:number,arg2:boolean):Promise<void>;
 
 export function SetPassphrase(arg1:string):Promise<void>;

frontend/wailsjs/go/main/App.js

@@ -1306,6 +1306,10 @@ export function LookupCallsignFresh(arg1) {
   return window['go']['main']['App']['LookupCallsignFresh'](arg1);
 }
 
+export function MotorNudgeKHz(arg1) {
+  return window['go']['main']['App']['MotorNudgeKHz'](arg1);
+}
+
 export function MotorReadElements() {
   return window['go']['main']['App']['MotorReadElements']();
 }
@@ -1314,6 +1318,10 @@ export function MotorSetElement(arg1, arg2) {
   return window['go']['main']['App']['MotorSetElement'](arg1, arg2);
 }
 
+export function MotorTuneKHz(arg1) {
+  return window['go']['main']['App']['MotorTuneKHz'](arg1);
+}
+
 export function MoveDatabase(arg1) {
   return window['go']['main']['App']['MoveDatabase'](arg1);
 }
@@ -1894,6 +1902,10 @@ export function SetKenwoodKeySpeed(arg1) {
   return window['go']['main']['App']['SetKenwoodKeySpeed'](arg1);
 }
 
+export function SetMotorFollow(arg1, arg2) {
+  return window['go']['main']['App']['SetMotorFollow'](arg1, arg2);
+}
+
 export function SetOpsLogQSLReceived(arg1, arg2) {
   return window['go']['main']['App']['SetOpsLogQSLReceived'](arg1, arg2);
 }