fix(ui): show the selected microphone's full name in the device tooltip (#1029) (#1037)

The Input Device dropdown has a fixed width and cuts labels off at about
18 characters. Raw ALSA names such as "sof-hda-dsp: - (hw:0,6)" therefore
all look like "sof-hda-dsp: - (h…", and the tooltip always showed the same
generic text, so there was no way to tell which entry was selected.

The tooltip now shows the full label of the selected device. It updates
when the list is filled and every time the selection changes, and goes
back to the generic hint for System Default.

src/vocalinux/ui/settings_dialog.py

@@ -2140,6 +2140,18 @@ def _combo_chrome(combo: Gtk.Widget, tooltip: Optional[str] = None) -> None:
     _prevent_scroll_on_hover(combo)
 
 
+_AUDIO_DEVICE_TOOLTIP = "Select the microphone to use for voice recognition"
+
+
+def _sync_audio_device_tooltip(combo: Gtk.ComboBoxText) -> None:
+    """Show the selected microphone's full name, which the fixed-width combo truncates."""
+    label = combo.get_active_text()
+    if not label or combo.get_active_id() in (None, "-1"):
+        combo.set_tooltip_text(_AUDIO_DEVICE_TOOLTIP)
+    else:
+        combo.set_tooltip_text(label)
+
+
 def _new_spin(
     lower: float, upper: float, step: float, digits: int, tooltip: Optional[str] = None
 ) -> Gtk.SpinButton:
@@ -3137,7 +3149,7 @@ class SettingsDialog(AboutSectionMixin):
         self.audio_device_combo = Gtk.ComboBoxText()
         _combo_chrome(
             self.audio_device_combo,
-            tooltip="Select the microphone to use for voice recognition",
+            tooltip=_AUDIO_DEVICE_TOOLTIP,
         )
 
         refresh_btn = Gtk.Button.new_from_icon_name("view-refresh-symbolic", Gtk.IconSize.BUTTON)
@@ -9925,6 +9937,7 @@ For now, the engine has been reverted to VOSK."""
                 if self.speech_engine is not None:
                     self.speech_engine.set_audio_device(None, None)
 
+        _sync_audio_device_tooltip(self.audio_device_combo)
         logger.info(f"Found {len(devices)} audio input devices")
 
     def _on_refresh_audio_devices(self, widget):
@@ -9934,6 +9947,7 @@ For now, the engine has been reverted to VOSK."""
 
     def _on_audio_device_changed(self, widget):
         """Handle changes in the selected audio device."""
+        _sync_audio_device_tooltip(self.audio_device_combo)
         if self._initializing:
             return