Finish xml doc comments (#58)

QUICK SUMMARY (TL;DR):
#48 XML comments add to repository

PR SOLUTION APPROACH:
Added tags for all classes, constructors, methods, properties,
properties, and class variables with public or protected scope. Created
extra branch for setup of docfx tool running successfully for next pr,
pending approval this one. Existing private members with xml comment
tags did not seem to appear in api generated documentation. Therefore
skipped further updating xml comment tags of private members.

---------

Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com>

Author: Jim-Johnson-Programmer

src/F23.StringSimilarity/Damerau.cs

@@ -56,6 +56,22 @@ public class Damerau : IMetricStringDistance, IMetricSpanDistance
         public double Distance(string s1, string s2)
             => Distance(s1.AsSpan(), s2.AsSpan());
 
+       /// <summary>
+       /// Calculates the Damerau-Levenshtein distance between two sequences.
+       /// </summary>
+       /// <remarks>The Damerau-Levenshtein distance is a metric for measuring the edit distance between
+       /// two sequences, allowing for the following operations: <list type="bullet"> <item><description>Insertion of a
+       /// single element.</description></item> <item><description>Deletion of a single element.</description></item>
+       /// <item><description>Substitution of one element for another.</description></item>
+       /// <item><description>Transposition of two adjacent elements.</description></item> </list> This method is
+       /// case-sensitive for sequences of strings or characters.</remarks>
+       /// <typeparam name="T">The type of elements in the sequences. Must implement <see cref="IEquatable{T}"/>.</typeparam>
+       /// <param name="s1">The first sequence to compare. Cannot be <see langword="null"/>.</param>
+       /// <param name="s2">The second sequence to compare. Cannot be <see langword="null"/>.</param>
+       /// <returns>The Damerau-Levenshtein distance between the two sequences, which represents the minimum number of operations
+       /// (insertions, deletions, substitutions, or transpositions) required to transform one sequence into the other.
+       /// Returns 0 if the sequences are equal.</returns>
+       /// <exception cref="ArgumentNullException">Thrown if <paramref name="s1"/> or <paramref name="s2"/> is <see langword="null"/>.</exception>
         public double Distance<T>(ReadOnlySpan<T> s1, ReadOnlySpan<T> s2)
             where T : IEquatable<T>
         {

src/F23.StringSimilarity/ICharacterSubstitution.cs

@@ -24,12 +24,14 @@
 
 namespace F23.StringSimilarity
 {
+    /// <summary>
     /// Used to indicate the cost of character substitution.
     ///
     /// Cost should always be in [0.0 .. 1.0]
     /// For example, in an OCR application, cost('o', 'a') could be 0.4
     /// In a checkspelling application, cost('u', 'i') could be 0.4 because these are
     /// next to each other on the keyboard...
+    /// </summary>
     public interface ICharacterSubstitution
     {
         /// <summary>

src/F23.StringSimilarity/Interfaces/INormalizedSpanDistance.cs

@@ -1,5 +1,8 @@
 namespace F23.StringSimilarity.Interfaces
 {
+    /// <summary>
+    /// An interface for normalized distance measures that operate on spans.
+    /// </summary>
     public interface INormalizedSpanDistance : ISpanDistance
     {
     }

src/F23.StringSimilarity/Interfaces/INormalizedSpanSimilarity.cs

@@ -1,5 +1,10 @@
 namespace F23.StringSimilarity.Interfaces
 {
+    /// <summary>
+    /// Defines a contract for calculating the similarity between spans of text, normalized to a range of 0 to 1.
+    /// </summary>
+    /// <remarks>This interface extends <see cref="ISpanSimilarity"/> by ensuring that similarity scores are
+    /// normalized. A score of 0 indicates no similarity, while a score of 1 indicates identical spans.</remarks>
     public interface INormalizedSpanSimilarity : ISpanSimilarity
     {
     }

src/F23.StringSimilarity/Interfaces/INormalizedStringDistance.cs

@@ -24,6 +24,9 @@
 
 namespace F23.StringSimilarity.Interfaces
 {
+    /// <summary>
+    /// Interface for normalized string distance algorithms.
+    /// </summary>
     public interface INormalizedStringDistance : IStringDistance
     {
     }

src/F23.StringSimilarity/Interfaces/INormalizedStringSimilarity.cs

@@ -24,6 +24,9 @@
 
 namespace F23.StringSimilarity.Interfaces
 {
+    /// <summary>
+    /// Interface for normalized string similarity algorithms.
+    /// </summary>
     public interface INormalizedStringSimilarity : IStringSimilarity
     {
     }

src/F23.StringSimilarity/Interfaces/ISpanDistance.cs

@@ -2,6 +2,9 @@
 
 namespace F23.StringSimilarity.Interfaces
 {
+    /// <summary>
+    /// An interface for distance measures that operate on spans.
+    /// </summary>
     public interface ISpanDistance
     {
         /// <summary>

src/F23.StringSimilarity/Interfaces/ISpanSimilarity.cs

@@ -2,6 +2,9 @@
 
 namespace F23.StringSimilarity.Interfaces
 {
+    /// <summary>
+    /// Interface for span similarity algorithms.
+    /// </summary>
     public interface ISpanSimilarity
     {
         /// <summary>

src/F23.StringSimilarity/Interfaces/IStringDistance.cs

@@ -24,6 +24,9 @@
 
 namespace F23.StringSimilarity.Interfaces
 {
+    /// <summary>
+    /// Interface for string distance algorithms.
+    /// </summary>
     public interface IStringDistance
     {
         /// <summary>

src/F23.StringSimilarity/Interfaces/IStringSimilarity.cs

@@ -24,6 +24,9 @@
 
 namespace F23.StringSimilarity.Interfaces
 {
+    /// <summary>
+    /// Interface for string similarity algorithms.
+    /// </summary>
     public interface IStringSimilarity
     {
         /// <summary>