Fix crash on attempting to edit particular beatmaps

Closes #29492.

I'm not immediately sure why this happened, but some old locally
modified beatmaps in my local realm database have a `BeatDivisor` of 0
stored, which is then passed to
`BindableBeatDivisor.SetArbitraryDivisor()`, which then blows up.

To stop this from happening, just refuse to use values outside of a sane
range.

osu.Game/Screens/Edit/BindableBeatDivisor.cs

@@ -16,6 +16,9 @@ public class BindableBeatDivisor : BindableInt
     {
         public static readonly int[] PREDEFINED_DIVISORS = { 1, 2, 3, 4, 6, 8, 12, 16 };
 
+        public const int MINIMUM_DIVISOR = 1;
+        public const int MAXIMUM_DIVISOR = 64;
+
         public Bindable<BeatDivisorPresetCollection> ValidDivisors { get; } = new Bindable<BeatDivisorPresetCollection>(BeatDivisorPresetCollection.COMMON);
 
         public BindableBeatDivisor(int value = 1)
@@ -30,8 +33,12 @@ public BindableBeatDivisor(int value = 1)
         /// </summary>
         /// <param name="divisor">The intended divisor.</param>
         /// <param name="preferKnownPresets">Forces changing the valid divisors to a known preset.</param>
-        public void SetArbitraryDivisor(int divisor, bool preferKnownPresets = false)
+        /// <returns>Whether the divisor was successfully set.</returns>
+        public bool SetArbitraryDivisor(int divisor, bool preferKnownPresets = false)
         {
+            if (divisor < MINIMUM_DIVISOR || divisor > MAXIMUM_DIVISOR)
+                return false;
+
             // If the current valid divisor range doesn't contain the proposed value, attempt to find one which does.
             if (preferKnownPresets || !ValidDivisors.Value.Presets.Contains(divisor))
             {
@@ -44,6 +51,7 @@ public void SetArbitraryDivisor(int divisor, bool preferKnownPresets = false)
             }
 
             Value = divisor;
+            return true;
         }
 
         private void updateBindableProperties()

osu.Game/Screens/Edit/Compose/Components/BeatDivisorControl.cs

@@ -330,14 +330,14 @@ protected override void LoadComplete()
 
             private void setPresetsFromTextBoxEntry()
             {
-                if (!int.TryParse(divisorTextBox.Text, out int divisor) || divisor < 1 || divisor > 64)
+                if (!int.TryParse(divisorTextBox.Text, out int divisor) || !BeatDivisor.SetArbitraryDivisor(divisor))
                 {
+                    // the text either didn't parse as a divisor, or the divisor was not set due to being out of range.
+                    // force a state update to reset the text box's value to the last sane value.
                     updateState();
                     return;
                 }
 
-                BeatDivisor.SetArbitraryDivisor(divisor);
-
                 this.HidePopover();
             }