Address code-review: ArgonAccuracyCounter format fallback, Playfield mods-cache lifetime comment, HitObjectContainer tie-breaker note

Agent-Logs-Url: https://github.com/winnerspiros/osu/sessions/cef46462-51dc-44c0-bfcc-44fa8a66c144

Co-authored-by: winnerspiros <1675249+winnerspiros@users.noreply.github.com>

Author: Copilot

osu.Game/Rulesets/UI/HitObjectContainer.cs

@@ -140,6 +140,11 @@ private void addDrawable(DrawableHitObject drawable)
             // Binary-search insertion to keep aliveObjectsSortedCache in StartTime order.
             // O(log n) search + O(n) shift — far cheaper than rebuilding & sorting
             // the entire list from scratch on every alive-state transition.
+            // Note: `<=` means new objects with the same StartTime are appended after
+            // existing ones (stable insertion order within a tie group).  The full
+            // visual-tree Compare also applies CompareReverseChildID as a tie-breaker,
+            // but AliveObjects consumers (e.g. cursor particles) don't require that
+            // level of ordering stability.
             double startTime = drawable.HitObject.StartTime;
             int lo = 0, hi = aliveObjectsSortedCache.Count;
 

osu.Game/Rulesets/UI/Playfield.cs

@@ -257,6 +257,8 @@ protected override void LoadComplete()
             mods = Mods?.ToArray();
 
             // Pre-filter once; avoids a per-frame `is IUpdatableByPlayfield` check on every mod.
+            // Mods are resolved once at construction and don't change during gameplay, so this
+            // cached slice is always valid for the lifetime of this Playfield.
             updatableByPlayfieldMods = mods?.OfType<IUpdatableByPlayfield>().ToArray()
                                        ?? Array.Empty<IUpdatableByPlayfield>();
 

osu.Game/Screens/Play/HUD/ArgonAccuracyCounter.cs

@@ -64,6 +64,12 @@ public LocalisableString Text
                         wholePart.Text = str[..dotIndex];
                         fractionPart.Text = str[dotIndex..pctIndex];
                     }
+                    else
+                    {
+                        // Fallback for unexpected format (e.g. localised strings without '.' or '%').
+                        wholePart.Text = str;
+                        fractionPart.Text = string.Empty;
+                    }
                 }
             }