Fix #2141: Enable write-related attributes on positional record constructor parameters

[SteveGuoh]

✅ Fixes #2141

✅ Problem

This PR resolves the issue where attributes like [Format], [Constant], and [Default] have no effect when applied to parameters in positional record constructors, particularly during WriteRecords() operations.

🔍 Original Issue Example (from JoshClose#2141)

Given the following record:

public record Person(string Name, [Format("yyyy-MM-dd")] DateTime Birthday);

And the following code:

var records = new List<Person>
{
    new("Alice", new DateTime(1990, 2, 1))
};

using var writer = new StringWriter();
using var csv = new CsvWriter(writer, CultureInfo.InvariantCulture);
csv.WriteRecords(records);

Console.WriteLine(writer.ToString());

❌ Actual Output (Before Fix)

Name,Birthday
Alice,2/1/1990 12:00:00 AM

✅ Expected Output (After Fix)

Name,Birthday
Alice,1990-02-01

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🛠️ Changes

• Ensures that mapping attributes applied to record constructor parameters are copied to their corresponding member maps during auto-mapping.
• Enables support for write-related attributes (FormatAttribute, ConstantAttribute, DefaultAttribute, etc.) on positional record constructor parameters.

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✅ Tests

• Added unit tests to verify reading and writing of records with attributes applied to constructor parameters.

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📦 Impact

• This enhancement improves CsvHelper's support for C# 9+ positional records.
• Allows developers to rely on attribute-based mapping even for simplified record types, reducing the need for verbose ClassMap definitions in many scenarios.