feat(qt): For You gains Qobuz Mixes pages, Artist Spotlight and Radios

Ports the three sections the tab was missing, against the Slint
implementation rather than invented: the section rails, the cards, and the
mix landing page with its navigation seam so back/forward behave.

The mixes reuse the shared crates for their requests -- the Slint app
already makes them, so nothing new talks to Qobuz here.

Also carries the qt-run.sh portability work needed for the Mac mini:
`free`, `nproc`, `pgrep` and `timeout` all differ or are simply absent on
BSD/macOS. Two of those bit during the first Mac build. `pgrep` exits 1
when it matches nothing -- the normal case -- and under `pipefail` that
killed the script before a single line of output, which reads exactly like
a build that did nothing. And `timeout` does not exist on macOS at all, so
the smoke produced a one-line log over which the grep cheerfully reported
"0 QML complaints": a test that never ran, rendering as a pass. The smoke
now fails outright on a log that short.

cc

crates/qbz-qt/qml/shell/PlayerBar.qml

@@ -102,7 +102,19 @@ Rectangle {
     // Favorite state of the now-playing track (Slint:
     // QueueState.now-playing-favorite). The queue document carries it on its
     // `current` row; this re-parses ONLY when that document changes.
+    //
+    // The bar's OWN heart settles fine on its own — `queue_qt::toggle_favorite`
+    // republishes the queue document straight after the write. What it could
+    // not see was a heart flipped ANYWHERE ELSE for the same track (the album
+    // page's row, a search result, a card): nothing republishes the queue for
+    // those, so the bar sat on a stale glyph for the rest of the track. The
+    // one-slot override below closes it, keyed on the track id so it expires
+    // by itself the moment playback moves on — no map to keep clean.
+    property string favOverrideId: ""
+    property bool favOverrideValue: false
     readonly property bool npFavorite: {
+        if (root.favOverrideId !== "" && root.favOverrideId === QbzPlayer.npTrackId)
+            return root.favOverrideValue
         try {
             var d = JSON.parse(QbzQueue.queueJson)
             return !!(d && d.current && d.current.isFavorite)
@@ -110,6 +122,16 @@ Rectangle {
             return false
         }
     }
+    Connections {
+        target: QbzLibrary
+        function onLibraryFavoriteChanged(key, value) {
+            var id = QbzPlayer.npTrackId
+            if (id !== "" && key === "track:" + id) {
+                root.favOverrideId = id
+                root.favOverrideValue = value
+            }
+        }
+    }
 
     // Audio settings / normalization (Tauri's normalization button; Slint's
     // "Audio settings" flyout). `normalization` IS settable through