fix: Remove AppendFormatted(string?) from interpolated handler

Removed the AppendFormatted(string?) method from CSharpInterpolatedStringHandler, as its functionality is now redundant. Also updated the #if NET6_0_OR_GREATER directive to wrap the namespace declaration for improved clarity and consistency.

Author: samtrion

src/NetEvolve.CodeBuilder/CSharpCodeBuilder.AppendInterpolated.cs

@@ -1,6 +1,6 @@
+#if NET6_0_OR_GREATER
 namespace NetEvolve.CodeBuilder;
 
-#if NET6_0_OR_GREATER
 using System.Globalization;
 using System.Runtime.CompilerServices;
 
@@ -165,19 +165,6 @@ public void AppendFormatted<T>(T value, int alignment, string? format)
         _owner.HandlerRawAppend(str);
     }
 
-    /// <summary>Appends a string value from the interpolated string.</summary>
-    /// <param name="value">The string to append.</param>
-    public void AppendFormatted(string? value)
-    {
-        if (string.IsNullOrEmpty(value))
-        {
-            return;
-        }
-
-        EnsureIndented();
-        _owner.HandlerRawAppend(value);
-    }
-
     /// <summary>Appends a <see cref="ReadOnlySpan{T}"/> value from the interpolated string.</summary>
     /// <param name="value">The span to append.</param>
     public void AppendFormatted(ReadOnlySpan<char> value)