feat: Bluetooth-mode dropdown in the control tab

Adds a dropdown (like the sleep-timer one) to switch operation mode
between Normal, Bluetooth speaker (sink) and Bluetooth headphones
(source) right from the control tab. Reuses setOperationMode()/the /mode
endpoint, so selecting a mode restarts the device into it; the button
highlights the active BT mode. New control.bt* locale keys in all langs.

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

Author: fhirschmann

README.md

@@ -86,6 +86,7 @@ neon logo that doubles as the SVG favicon ([`8d9725c`](../../commit/8d9725c)):
 | Bluetooth modes can be stopped from the web interface; commands 143/144 switch modes directly via buttons | [`0c3edd0`](../../commit/0c3edd0) |
 | Button lock (Kindersicherung) toggle directly in the control tab of the web interface with visual lock status indicator | [`ae83116`](../../commit/ae83116) |
 | Control buttons (single-track Repeat toggle, Sleep-Timer with dropdown and live remaining countdown, Night Mode/Dimming) directly in the control tab of the web interface | [`6918d36`](../../commit/6918d36) |
+| Bluetooth-mode dropdown in the control tab (Normal / Speaker / Headphones), mirroring the sleep-timer dropdown; selecting a mode restarts the device into it and the button highlights the active BT mode | [`b9f1e5c`](../../commit/b9f1e5c) |
 
 #### Feature highlights
 

html/locales/de.json

@@ -160,6 +160,10 @@
 		"command": "Modifikation ausführen",
 		"locked": "Gesperrt",
 		"unlocked": "Entsperrt",
+		"btMode": "Bluetooth",
+		"btNormal": "Normal",
+		"btSpeaker": "Lautsprecher",
+		"btHeadphones": "Kopfhörer",
 		"nightOn": "Nacht An",
 		"nightOff": "Nacht Aus",
 		"repeatOff": "Aus",

html/locales/en.json

@@ -161,6 +161,10 @@
 		"command": "Execute Modification",
 		"locked": "Locked",
 		"unlocked": "Unlocked",
+		"btMode": "Bluetooth",
+		"btNormal": "Normal",
+		"btSpeaker": "Speaker",
+		"btHeadphones": "Headphones",
 		"nightOn": "Night On",
 		"nightOff": "Night Off",
 		"repeatOff": "Off",

html/locales/fr.json

@@ -153,6 +153,10 @@
 		"command": "Exécuter la modification",
 		"locked": "Verrouillé",
 		"unlocked": "Déverrouillé",
+		"btMode": "Bluetooth",
+		"btNormal": "Normal",
+		"btSpeaker": "Enceinte",
+		"btHeadphones": "Casque",
 		"nightOn": "Nuit On",
 		"nightOff": "Nuit Off",
 		"repeatOff": "Off",

html/management.html

@@ -1752,6 +1752,18 @@ <h5 class="modal-title" data-i18n="tools.nvs.erase.title"></h5>
 								<span id="ico-night-mode" class="fas fa-moon"></span>
 								<span id="lbl-night-mode" class="d-none d-sm-inline" data-i18n="control.nightOff">Night Off</span>
 							</button>
+							<!-- Bluetooth Mode Dropdown -->
+							<div class="dropdown d-inline-flex align-items-center">
+								<button type="button" class="btn btn-sm cp-control-button dropdown-toggle" id="btn-bt-mode" data-bs-toggle="dropdown" aria-expanded="false">
+									<span class="fab fa-bluetooth-b"></span>
+									<span id="lbl-bt-mode" class="d-none d-sm-inline" data-i18n="control.btMode">Bluetooth</span>
+								</button>
+								<ul class="dropdown-menu dropdown-menu-dark dropdown-menu-end" aria-labelledby="btn-bt-mode" style="border: 1px solid var(--cp-border); background: var(--cp-panel); margin-top: 5px;">
+									<li><a class="dropdown-item" href="#" onclick="setOperationMode(0)" data-i18n="control.btNormal">Normal</a></li>
+									<li><a class="dropdown-item" href="#" onclick="setOperationMode(1)" data-i18n="control.btSpeaker">Speaker</a></li>
+									<li><a class="dropdown-item" href="#" onclick="setOperationMode(2)" data-i18n="control.btHeadphones">Headphones</a></li>
+								</ul>
+							</div>
 							<!-- Key Lock Button -->
 							<button type="button" class="btn btn-sm cp-lock-button unlocked" id="btn-lock-controls" onclick="sendControl(100)">
 								<span id="ico-lock-controls" class="fas fa-lock-open"></span>
@@ -3825,6 +3837,25 @@ <h5 class="modal-title" data-i18n="tools.nvs.erase.title"></h5>
 			if (btTab) {
 				btTab.classList.toggle('bt-active', opmode === 1 || opmode === 2);
 			}
+
+			// Control-tab Bluetooth-mode dropdown button
+			const btBtn = document.getElementById('btn-bt-mode');
+			const btLbl = document.getElementById('lbl-bt-mode');
+			if (btBtn && btLbl) {
+				if (opmode === 1) {
+					btBtn.className = "btn btn-sm cp-control-button active-magenta dropdown-toggle";
+					btLbl.setAttribute('data-i18n', 'control.btSpeaker');
+					btLbl.innerHTML = i18next.t("control.btSpeaker", "Speaker");
+				} else if (opmode === 2) {
+					btBtn.className = "btn btn-sm cp-control-button active-magenta dropdown-toggle";
+					btLbl.setAttribute('data-i18n', 'control.btHeadphones');
+					btLbl.innerHTML = i18next.t("control.btHeadphones", "Headphones");
+				} else {
+					btBtn.className = "btn btn-sm cp-control-button dropdown-toggle";
+					btLbl.setAttribute('data-i18n', 'control.btMode');
+					btLbl.innerHTML = i18next.t("control.btMode", "Bluetooth");
+				}
+			}
 		} function connect() {
 			socket = new WebSocket("ws://" + host + "/ws");
 			socket.onopen = function () {