Phase 3 (WA2e): move web Freq/FreqA handlers into the adapter

With ApplyVfoA now a thin SetVfoA delegate (channel orchestration on the
OnAfterTune hook), the web Freq/FreqA handlers carry no MainForm logic — move
them to TWebAdapter.OnFreq (active-VFO routing → SetVfoA/SetVfoB) and OnFreqA
(SetVfoA). CAT freq (CATSetVfoA/SyncCATVfoA) left as-is — moves with the CAT
adapter (Phase 4).

Remaining host-coupled web handlers: Run / Connect / device CRUD (daemon entry).

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

WebAdapter.pas

@@ -56,6 +56,8 @@ type
     procedure SyncNB;
     procedure SyncSNB;
     procedure SyncANF;
+    procedure SyncFreq;
+    procedure SyncFreqA;
     procedure SyncFreqB;
     procedure SyncCenter;
     procedure SyncAttn;
@@ -85,6 +87,8 @@ type
     procedure OnNB(Mode: Integer);
     procedure OnSNB(On_: Boolean);
     procedure OnANF(On_: Boolean);
+    procedure OnFreq(Hz: Double);
+    procedure OnFreqA(Hz: Double);
     procedure OnFreqB(Hz: Double);
     procedure OnCenter(Hz: Double);
     procedure OnAttn(Idx: Integer);
@@ -258,6 +262,23 @@ begin FSyncBool := On_; FController.Invoke(@SyncANF); end;
 procedure TWebAdapter.SyncANF;
 begin FController.SetANF(FSyncBool); end;
 
+procedure TWebAdapter.OnFreq(Hz: Double);
+begin FSyncFreq := Hz; FController.Invoke(@SyncFreq); end;
+
+procedure TWebAdapter.SyncFreq;
+begin
+  // "freq" для АКТИВНОГО VFO. SetVfoA/SetVfoB несут CTUN/band-detect/сеть +
+  // канальную оркестрацию (через OnAfterTune-хук); рендер — rfVfoA/rfVfoB.
+  if FController.FActiveVfo = 0 then FController.SetVfoA(FSyncFreq)
+  else                              FController.SetVfoB(FSyncFreq);
+end;
+
+procedure TWebAdapter.OnFreqA(Hz: Double);
+begin FSyncFreq := Hz; FController.Invoke(@SyncFreqA); end;
+
+procedure TWebAdapter.SyncFreqA;
+begin FController.SetVfoA(FSyncFreq); end;
+
 procedure TWebAdapter.OnFreqB(Hz: Double);
 begin FSyncFreq := Hz; FController.Invoke(@SyncFreqB); end;