fix editing non-timed annotations

Azaion.Annotator/DTO/FormState.cs

@@ -24,19 +24,18 @@ public class FormState
     public TimeSpan? GetTime(string name)
     {
         var timeStr = name.Split("_").LastOrDefault();
-        if (string.IsNullOrEmpty(timeStr))
+        if (string.IsNullOrEmpty(timeStr) || timeStr.Length < 7)
             return null;
-        
-        try
-        {
-            //For some reason, TimeSpan.ParseExact doesn't work on every platform.
-            return new TimeSpan(
-                days: 0,
-                hours: int.Parse(timeStr[0..1]),
-                minutes: int.Parse(timeStr[1..3]),
-                seconds: int.Parse(timeStr[3..5]),
-                milliseconds: int.Parse(timeStr[5..6]) * 100);
-        }
-        catch (Exception e) {  return null;  }
+
+        //For some reason, TimeSpan.ParseExact doesn't work on every platform.
+        if (!int.TryParse(timeStr[0..1], out var hours))
+            return null;
+        if (!int.TryParse(timeStr[1..3], out var minutes))
+            return null;
+        if (!int.TryParse(timeStr[3..5], out var seconds))
+            return null;
+        if (!int.TryParse(timeStr[5..6], out var milliseconds))
+            return null;
+        return new TimeSpan(0, hours, minutes, seconds, milliseconds * 100);
     }
 }