Add EventOccurrenceParserService and update service registrations

Registered the new EventOccurrenceParserService in Program.cs to handle event occurrence parsing. Updated the _Imports.razor file to reflect the renaming of the EventCalendar component to Calendar. Removed the obsolete EventCalendar component to streamline the codebase.

Core/Models/EventOccurrenceParseResult.cs

@@ -0,0 +1,37 @@
+using Core.Entities;
+
+namespace Core.Models;
+
+/// <summary>
+/// Result of parsing event occurrence text data.
+/// Contains parsed occurrences, errors, and warnings.
+/// </summary>
+public class EventOccurrenceParseResult
+{
+    /// <summary>
+    /// Dictionary of parsed event occurrences, keyed by EventDefinition.
+    /// For special events (GeneralSchedule/VotingDelegates), the EventDefinition key will be the static instance.
+    /// </summary>
+    public IDictionary<EventDefinition, List<EventOccurrence>> Occurrences { get; set; } = new Dictionary<EventDefinition, List<EventOccurrence>>();
+
+    /// <summary>
+    /// List of parsing errors (critical issues that prevented parsing).
+    /// </summary>
+    public List<string> Errors { get; set; } = new();
+
+    /// <summary>
+    /// List of parsing warnings (non-critical issues that occurred during parsing).
+    /// </summary>
+    public List<string> Warnings { get; set; } = new();
+
+    /// <summary>
+    /// Total number of event occurrences successfully parsed.
+    /// </summary>
+    public int TotalParsed => Occurrences.Values.Sum(list => list.Count);
+
+    /// <summary>
+    /// Indicates whether parsing was successful (no errors).
+    /// </summary>
+    public bool IsSuccess => Errors.Count == 0;
+}
+