[fix](trx-frontend): let decoder disable take scheduler control

When a scheduler-managed decoder is manually disabled from the frontend,
take scheduler control first so the manual change overrides the current
scheduler cycle like a direct frequency change does.

Track decoder enabled state on the toggle buttons and only take over
when the click is actually disabling FT8, FT4, FT2, WSPR, or HF APRS.

Co-Authored-By: OpenAI Codex <noreply@openai.com>
Signed-off-by: Stanislaw Grams <stanislawgrams@gmail.com>

src/trx-client/trx-frontend/trx-frontend-http/assets/web/plugins/ft2.js

@@ -179,8 +179,14 @@ if (ft2FilterInput) {
   });
 }
 
-document.getElementById("ft2-decode-toggle-btn")?.addEventListener("click", async () => {
-  try { await postPath("/toggle_ft2_decode"); } catch (e) { console.error("FT2 toggle failed", e); }
+const ft2DecodeToggleBtn = document.getElementById("ft2-decode-toggle-btn");
+ft2DecodeToggleBtn?.addEventListener("click", async () => {
+  try {
+    await window.takeSchedulerControlForDecoderDisable?.(ft2DecodeToggleBtn);
+    await postPath("/toggle_ft2_decode");
+  } catch (e) {
+    console.error("FT2 toggle failed", e);
+  }
 });
 
 document.getElementById("settings-clear-ft2-history")?.addEventListener("click", async () => {

src/trx-client/trx-frontend/trx-frontend-http/assets/web/plugins/ft4.js

@@ -179,8 +179,14 @@ if (ft4FilterInput) {
   });
 }
 
-document.getElementById("ft4-decode-toggle-btn")?.addEventListener("click", async () => {
-  try { await postPath("/toggle_ft4_decode"); } catch (e) { console.error("FT4 toggle failed", e); }
+const ft4DecodeToggleBtn = document.getElementById("ft4-decode-toggle-btn");
+ft4DecodeToggleBtn?.addEventListener("click", async () => {
+  try {
+    await window.takeSchedulerControlForDecoderDisable?.(ft4DecodeToggleBtn);
+    await postPath("/toggle_ft4_decode");
+  } catch (e) {
+    console.error("FT4 toggle failed", e);
+  }
 });
 
 document.getElementById("settings-clear-ft4-history")?.addEventListener("click", async () => {

src/trx-client/trx-frontend/trx-frontend-http/assets/web/plugins/ft8.js

@@ -447,8 +447,14 @@ if (ft8MessagesEl) {
   });
 }
 
-document.getElementById("ft8-decode-toggle-btn").addEventListener("click", async () => {
-  try { await postPath("/toggle_ft8_decode"); } catch (e) { console.error("FT8 toggle failed", e); }
+const ft8DecodeToggleBtn = document.getElementById("ft8-decode-toggle-btn");
+ft8DecodeToggleBtn?.addEventListener("click", async () => {
+  try {
+    await window.takeSchedulerControlForDecoderDisable?.(ft8DecodeToggleBtn);
+    await postPath("/toggle_ft8_decode");
+  } catch (e) {
+    console.error("FT8 toggle failed", e);
+  }
 });
 
 document.getElementById("settings-clear-ft8-history")?.addEventListener("click", async () => {

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

@@ -372,8 +372,14 @@ window.restoreHfAprsHistory = function(packets) {
   window.onServerHfAprsBatch(packets);
 };
 
-document.getElementById("hf-aprs-decode-toggle-btn")?.addEventListener("click", async () => {
-  try { await postPath("/toggle_hf_aprs_decode"); } catch (e) { console.error("HF APRS toggle failed", e); }
+const hfAprsDecodeToggleBtn = document.getElementById("hf-aprs-decode-toggle-btn");
+hfAprsDecodeToggleBtn?.addEventListener("click", async () => {
+  try {
+    await window.takeSchedulerControlForDecoderDisable?.(hfAprsDecodeToggleBtn);
+    await postPath("/toggle_hf_aprs_decode");
+  } catch (e) {
+    console.error("HF APRS toggle failed", e);
+  }
 });
 
 document.getElementById("settings-clear-hf-aprs-history")?.addEventListener("click", async () => {

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

@@ -111,6 +111,7 @@ async function vchanTakeSchedulerControl() {
     console.error("scheduler control takeover failed", e);
   }
 }
+window.vchanTakeSchedulerControl = vchanTakeSchedulerControl;
 
 // Called by app.js when the SSE `session` event arrives.
 function vchanHandleSession(data) {

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

@@ -255,8 +255,14 @@ if (wsprMessagesEl) {
   });
 }
 
-document.getElementById("wspr-decode-toggle-btn").addEventListener("click", async () => {
-  try { await postPath("/toggle_wspr_decode"); } catch (e) { console.error("WSPR toggle failed", e); }
+const wsprDecodeToggleBtn = document.getElementById("wspr-decode-toggle-btn");
+wsprDecodeToggleBtn?.addEventListener("click", async () => {
+  try {
+    await window.takeSchedulerControlForDecoderDisable?.(wsprDecodeToggleBtn);
+    await postPath("/toggle_wspr_decode");
+  } catch (e) {
+    console.error("WSPR toggle failed", e);
+  }
 });
 
 document.getElementById("settings-clear-wspr-history")?.addEventListener("click", async () => {