[feat](trx-frontend-http): disable plugin enable/disable for rx role

Disable plugin toggle buttons for rx-authenticated users:
- FT8 decode toggle
- WSPR decode toggle
- CW auto checkbox

RX users cannot enable/disable decoders, preventing unintended
configuration changes.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
Signed-off-by: Stanislaw Grams <stanislawgrams@gmail.com>

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

@@ -155,6 +155,21 @@ function applyAuthRestrictions() {
     if (jogWheel) jogWheel.style.opacity = "0.5";
     jogButtons.forEach(btn => btn.disabled = true);
 
+    // Disable plugin enable/disable buttons
+    const pluginToggleBtns = [
+      "ft8-decode-toggle-btn",
+      "wspr-decode-toggle-btn",
+      "cw-auto"
+    ];
+    pluginToggleBtns.forEach(id => {
+      const btn = document.getElementById(id);
+      if (btn && btn.tagName === "BUTTON") {
+        btn.disabled = true;
+      } else if (btn && btn.type === "checkbox") {
+        btn.disabled = true;
+      }
+    });
+
     // Hide TX-specific UI but keep controls visible (disabled)
     if (txLimitRow) txLimitRow.style.opacity = "0.5";
   }