feat: QO-100 NB transponder bandplan overlay on spectrum

Add a thin colored strip along the bottom of the spectrum (above the
ruler) showing the QO-100 narrow-band transponder bandplan: mode
segments (CW ONLY / NB DIGI / DIGI / SSB / MIXED MODES) plus the three
beacons (CW / PSK / EXP) as muted-red cells at their ranges.

- New unit BandPlanOverlay.pas (TBandPlanOverlay), modelled on
  VfoOverlay: content rendered once into a cache bitmap, per-frame cost
  is just a constant-alpha composite (CPU) / one textured quad (GL).
  Cache invalidates only on view change (center/span/width) so it idles
  while the QO-100 downlink display is static.
- Wired into both render paths: SpectrumView (CPU composite) and
  SpectrumViewOpengl (texture, re-uploaded only when dirty).
- MainForm: SetView fed from SyncSpecViewFreq; visibility gated by
  InQO100 (Pluto + full-duplex transponder), like RX MUTE / BEACON.
- DPI-robust: strip height scales with Screen.PixelsPerInch and the font
  height is tied to the strip height (not point size), so labels always
  fit at any Windows scaling.
- Segment/beacon frequencies and colors are a single editable table.

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

SpectrumViewOpengl.pas

@@ -17,7 +17,7 @@ interface
 uses
   Classes, SysUtils, Graphics, Controls, Math, Types,
   OpenGLContext, GL,
-  AppTheme, SpectrumView, VfoOverlay, WaterfallViewOpengl;
+  AppTheme, SpectrumView, VfoOverlay, BandPlanOverlay, WaterfallViewOpengl;
 
 type
   TGLTextureCache = record
@@ -34,6 +34,7 @@ type
     FOverlayDirty: Boolean;
     FSampleOverlayDirty: Boolean;
     FVfoOverlayDirty: Boolean;
+    FBandOverlayDirty: Boolean;
     FGridLabelTex: TGLTextureCache;
     FAGCLabelTex: TGLTextureCache;
     FAGCHangLabelTex: TGLTextureCache;
@@ -41,6 +42,7 @@ type
     FADCOverlayTex: TGLTextureCache;
     FSampleOverlayTex: TGLTextureCache;
     FVfoOverlayTex: TGLTextureCache;
+    FBandOverlayTex: TGLTextureCache;
     FLastAGCText: string;
     FLastAGCY: Integer;
     FLastAGCHangY: Integer;
@@ -55,6 +57,9 @@ type
     FLastVfoY: Integer;
     FLastVfoW: Integer;
     FLastVfoH: Integer;
+    FLastBandW: Integer;
+    FLastBandCenter: Double;
+    FLastBandSpan: Double;
     FGLSpectrumW: Integer;
     FGLSpectrumH: Integer;
     FSpY: array of Integer;
@@ -123,6 +128,9 @@ begin
   FOverlayDirty := True;
   FSampleOverlayDirty := True;
   FVfoOverlayDirty := True;
+  FBandOverlayDirty := True;
+  FLastBandW := -MaxInt;
+  FLastBandCenter := -1; FLastBandSpan := -1;
   FLastAGCY := -MaxInt;
   FLastAGCHangY := -MaxInt;
   FLastMarkerX := -MaxInt;
@@ -140,6 +148,7 @@ begin
     DeleteTexture(FADCOverlayTex);
     DeleteTexture(FSampleOverlayTex);
     DeleteTexture(FVfoOverlayTex);
+    DeleteTexture(FBandOverlayTex);
   end;
   inherited Destroy;
 end;
@@ -720,6 +729,29 @@ var
   B: TBitmap;
   OW, OH: Integer;
 begin
+  // Бэндплан QO-100 — полоска внизу спектра (над ruler), под панелями оверлеев.
+  if Assigned(BandPlanOverlay) and BandPlanOverlay.Active then
+  begin
+    if FOverlayDirty or FBandOverlayDirty or FBandOverlayTex.Dirty or
+       (FLastBandW <> W) or
+       (Abs(FLastBandCenter - BandPlanOverlay.CenterFreq) >= 1.0) or
+       (Abs(FLastBandSpan - BandPlanOverlay.SpanHz) >= 1.0) then
+    begin
+      B := TBitmap.Create;
+      try
+        BandPlanOverlay.DrawOverlayBitmap(B, W);
+        UploadBitmap(FBandOverlayTex, B, False, BANDPLAN_ALPHA);
+      finally
+        B.Free;
+      end;
+      FLastBandW := W;
+      FLastBandCenter := BandPlanOverlay.CenterFreq;
+      FLastBandSpan := BandPlanOverlay.SpanHz;
+      FBandOverlayDirty := False;
+    end;
+    DrawTexture(FBandOverlayTex, 0, H - FBandOverlayTex.H);
+  end;
+
   if Assigned(FSampleRateOverlay) then
   begin
     OW := Min(FSampleRateOverlay.Width, W - FSampleRateOverlay.Left);