fix(audio): scope stream volume overrides per media identity

Modules/Toast/ToastScreen.qml

@@ -46,7 +46,7 @@ Item {
     quickSwitchTimer.stop();
   }
 
-  function dismissToast(){
+  function dismissToast() {
     if (windowLoader.item) {
       hideTimer.stop();
       windowLoader.item.hideToast();

Services/Media/AudioService.qml

@@ -307,7 +307,7 @@ Singleton {
     objects: [...root.sinks, ...root.sources]
   }
 
-  // Per-app volume persistence (survives stream recreation on track change/seek)
+  // Per-stream volume overrides (app + media identity) so concurrent browser streams do not share one entry.
   property var appVolumeOverrides: ({})
   property var _knownAppStreamIds: ({})
   property bool _isApplyingAppOverride: false
@@ -360,21 +360,41 @@ Singleton {
       return "";
     }
     var props = node.properties;
+    var base = "";
     var binary = props["application.process.binary"] || "";
     if (binary) {
       var parts = binary.split("/");
-      return parts[parts.length - 1].toLowerCase();
+      base = parts[parts.length - 1].toLowerCase();
     }
-    var appName = props["application.name"] || "";
-    if (appName) {
-      return appName.toLowerCase();
+    if (!base) {
+      var appName = props["application.name"] || "";
+      if (appName) {
+        base = appName.toLowerCase();
+      }
     }
-    var appId = props["application.id"] || "";
-    if (appId) {
-      return appId.toLowerCase();
+    if (!base) {
+      var appId = props["application.id"] || "";
+      if (appId) {
+        base = appId.toLowerCase();
+      }
+    }
+    if (!base) {
+      return "";
     }
 
-    return "";
+    var mediaName = (props["media.name"] || "").trim().toLowerCase();
+    var mediaRole = (props["media.role"] || "").trim().toLowerCase();
+    var tagParts = [];
+    if (mediaName) {
+      tagParts.push(mediaName);
+    }
+    if (mediaRole) {
+      tagParts.push(mediaRole);
+    }
+    if (tagParts.length > 0) {
+      return base + "\u001f" + tagParts.join("\u001e");
+    }
+    return base + "\u001f" + String(node.id);
   }
 
   function setAppStreamVolume(appKey: string, volume: real): void {

Services/UI/ToastService.qml

@@ -10,7 +10,7 @@ Singleton {
   // actionLabel: optional label for clickable action link
   // actionCallback: optional function to call when action is clicked
   signal notify(string title, string description, string icon, string type, int duration, string actionLabel, var actionCallback)
-  signal dismiss()
+  signal dismiss
 
   // Convenience methods
   function showNotice(title, description = "", icon = "", duration = 3000, actionLabel = "", actionCallback = null) {
@@ -25,7 +25,7 @@ Singleton {
     notify(title, description, "", "error", duration, actionLabel, actionCallback);
   }
 
-  function dismissToast(){
+  function dismissToast() {
     dismiss();
   }
 }