feat: add optional student nickname for informal display

Keep legal first and last names for formal lists; show DisplayFirstName on teams, calendars, and import matching so two Josiahs can be told apart.

Co-authored-by: Cursor <cursoragent@cursor.com>

Core/Parsers/AssignmentRequirementParser.cs

@@ -9,6 +9,10 @@ public class AssignmentRequirementParser : CsvParserBase
 	{
 	}
 
+	public AssignmentRequirementParser(StreamReader reader, bool ignoreBlankLines = true) : base(reader, ignoreBlankLines)
+	{
+	}
+
 	public AssignmentRequirement[] Parse(ICollection<EventDefinition> events, ICollection<Student> students)
 	{
 		var assumptions = new List<AssignmentRequirement>();
@@ -20,7 +24,11 @@ public class AssignmentRequirementParser : CsvParserBase
 
 		var studentArray = 
             studentColumns
-                .Select(c => students.FirstOrDefault(s => s.FirstName == c)).ToArray();
+                .Select(c => students.FirstOrDefault(s =>
+                    string.Equals(s.DisplayFirstName, c, StringComparison.OrdinalIgnoreCase)
+                    || string.Equals(s.Nickname, c, StringComparison.OrdinalIgnoreCase)
+                    || string.Equals(s.FirstName, c, StringComparison.OrdinalIgnoreCase)))
+                .ToArray();
 
 		while (CsvReader.Read())
 		{

Core/Parsers/FuzzyStudentMatcher.cs

@@ -23,7 +23,14 @@ public static class FuzzyStudentMatcher
 
     public static int Score(Student student, string name)
     {
-        var candidates = new[] { student.Name, student.FirstNameLastName, student.LastNameFirstName };
+        var candidates = new[]
+        {
+            student.Name,
+            student.FirstNameLastName,
+            student.LastNameFirstName,
+            student.DisplayFirstName,
+            student.Nickname
+        }.Where(c => !string.IsNullOrWhiteSpace(c));
         return candidates.Max(candidate => Math.Max(Fuzz.Ratio(candidate, name), Fuzz.TokenSetRatio(candidate, name)));
     }
 }

Core/Parsers/TeamParser.cs

@@ -56,6 +56,10 @@ namespace Core.Parsers
 		{
 		}
 
+		public TeamParser(StreamReader reader, bool ignoreBlankLines = true) : base(reader, ignoreBlankLines)
+		{
+		}
+
 		public Team[] Parse(ICollection<EventDefinition> events, ICollection<Student> students)
 		{
 			var teams = new List<Team>();
@@ -118,7 +122,9 @@ namespace Core.Parsers
 						{
 							Fuzz.Ratio(s.Name, studentName),
 							Fuzz.Ratio(s.FirstNameLastName, studentName),
-							Fuzz.Ratio(s.FirstName, studentName)
+							Fuzz.Ratio(s.FirstName, studentName),
+							Fuzz.Ratio(s.DisplayFirstName, studentName),
+							string.IsNullOrWhiteSpace(s.Nickname) ? 0 : Fuzz.Ratio(s.Nickname, studentName)
 						}.Max()
 						where rat > 90
 						orderby rat descending