feat: add up/down arrow key bindings for playback speed control

auditui/app.py

@@ -43,6 +43,8 @@ class Auditui(App):
         ("right", "seek_forward", "+30s"),
         ("ctrl+left", "previous_chapter", "Previous chapter"),
         ("ctrl+right", "next_chapter", "Next chapter"),
+        ("up", "increase_speed", "Increase speed"),
+        ("down", "decrease_speed", "Decrease speed"),
         ("d", "toggle_download", "Download/Delete"),
         ("q", "quit", "Quit"),
     ]
@@ -124,6 +126,14 @@ class Auditui(App):
                 event.prevent_default()
                 self.action_seek_forward()
                 return
+            elif event.key == "up":
+                event.prevent_default()
+                self.action_increase_speed()
+                return
+            elif event.key == "down":
+                event.prevent_default()
+                self.action_decrease_speed()
+                return
 
         if isinstance(self.focused, DataTable):
             if event.key == "enter":
@@ -290,6 +300,16 @@ class Auditui(App):
         if not self.playback.seek_to_previous_chapter():
             self._no_playback_message()
 
+    def action_increase_speed(self) -> None:
+        """Increase playback speed."""
+        if not self.playback.increase_speed():
+            self._no_playback_message()
+
+    def action_decrease_speed(self) -> None:
+        """Decrease playback speed."""
+        if not self.playback.decrease_speed():
+            self._no_playback_message()
+
     def _no_playback_message(self) -> None:
         """Show message when no playback is active."""
         self.update_status("No playback active. Press Enter to play a book.")