[fix](trx-frontend-http): stabilize signal strength field width and BW overlay positioning

Increase sig-strength-display min-width to 7.5rem so the field no longer
resizes when the value switches between two-digit and three-digit numbers.

Reposition the fast BW overlay immediately when bandwidth changes arrive
via SSE, and force-display on bookmark apply so freq+bw render atomically
instead of the BW bars wiggling from a stale intermediate state.

https://claude.ai/code/session_01R2XBFEBL8CrsTx5inu25MA
Signed-off-by: Claude <noreply@anthropic.com>

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

@@ -2969,6 +2969,8 @@ function render(update) {
     currentBandwidthHz = update.filter.bandwidth_hz;
     window.currentBandwidthHz = currentBandwidthHz;
     syncBandwidthInput(currentBandwidthHz);
+    // Reposition BW overlay immediately so freq+bw render together.
+    positionFastOverlay(lastFreqHz, currentBandwidthHz);
     if (window.refreshCwTonePicker) {
       window.refreshCwTonePicker();
     }

src/trx-client/trx-frontend/trx-frontend-http/assets/web/plugins/bookmarks.js

@@ -388,7 +388,8 @@ async function bmApply(bm) {
         ++_freqOptimisticSeq;
         _freqOptimisticHz = bm.freq_hz;
       }
-      applyLocalTunedFrequency(bm.freq_hz);
+      // Force display so the BW overlay is repositioned even when freq is unchanged.
+      applyLocalTunedFrequency(bm.freq_hz, true);
     }
     if (typeof scheduleSpectrumDraw === "function" && typeof lastSpectrumData !== "undefined" && lastSpectrumData) {
       scheduleSpectrumDraw();

src/trx-client/trx-frontend/trx-frontend-http/assets/web/style.css

@@ -629,7 +629,7 @@ button:disabled { opacity: 0.6; cursor: not-allowed; }
   flex-shrink: 0;
 }
 .sig-strength-display {
-  min-width: 5.2rem;
+  min-width: 7.5rem;
   height: 3.35rem;
   padding: 0 0.7rem;
   border: 1px solid var(--border-light);