[feat](trx-frontend-http): centre the radio controls, split off the mode row

The controls every rig has — mode, wheel, tune step, transmit — now sit
as a centred block rather than packed against the left edge.

What the current mode adds moves out from among them: WFM's six controls
stretched the row sideways whenever it was active, pushing the wheel and
the step pickers off centre, and SAM did the same on a smaller scale.
They get a row of their own below a divider, which appears and leaves
with them — an empty one would still take a track and a gap in the tray
and draw its divider under controls it has nothing to do with.

Signed-off-by: Stan Grams <sjg@haxx.space>

src/trx-client/trx-frontend/trx-frontend-http/assets/web/generated/app.js

@@ -6201,6 +6201,7 @@ var wfmCciValEl = document.getElementById("wfm-cci-val");
 var wfmAciFillEl = document.getElementById("wfm-aci-fill");
 var wfmAciValEl = document.getElementById("wfm-aci-val");
 var samControlsCol = document.getElementById("sam-controls-col");
+var modeControlsRow = document.getElementById("mode-controls-row");
 var samStereoWidthEl = document.getElementById("sam-stereo-width");
 var samCarrierSyncEl = document.getElementById("sam-carrier-sync");
 var sdrSquelchWrapEl = document.getElementById("sdr-squelch-wrap");
@@ -6508,6 +6509,7 @@ function updateWfmControls() {
   const mode = (modeEl && modeEl.value ? modeEl.value : "").toUpperCase();
   if (wfmControlsCol) wfmControlsCol.style.display = mode === "WFM" ? "" : "none";
   if (samControlsCol) samControlsCol.style.display = mode === "SAM" ? "" : "none";
+  if (modeControlsRow) modeControlsRow.style.display = mode === "WFM" || mode === "SAM" ? "" : "none";
 }
 if (!hasWebCodecs) {
   rxAudioBtn.disabled = true;