[API Proposal]: Introduce extensions for all AlternateLookup built in collections and key String

Start by reviewing the proposed DictionaryExtensions API and the referenced issue #110505 about DefaultInterpolatedStringHandler. Compare the proposal with the built-in collections supporting AlternateLookup and determine the scope for extending them and key String. Done means the API design is resolved for the requested collection operations.

Background and motivation

I would like to propose an extension for all collections that are supporting AlternateLookup. For example Dictionary<string, TValue>.
It will use DefaultInterpolatedStringHandler as key and once this is merged, can became allocation free only with recompiling code to .NET 10.

API Proposal

namespace System.Collections.Generic;

public static class DictionaryExtensions
{
	public static bool TryGetValue<TValue>(this Dictionary<string, TValue> dictionary, ref DefaultInterpolatedStringHandler key, out TValue value)
	{
		if (dictionary.TryGetAlternateLookup(out Dictionary<string, TValue>.AlternateLookup<ReadOnlySpan<char>> span))
		{
			var result = span.TryGetValue(key.Text, out value);
			key.Clear();
			return result;
		}

		return dictionary.TryGetValue(key.ToStringAndClear(), out value);
	}

	public static bool TryAdd<TValue>(this Dictionary<string, TValue> dictionary, ref DefaultInterpolatedStringHandler key, TValue value)
	{
		if (dictionary.TryGetAlternateLookup(out Dictionary<string, TValue>.AlternateLookup<ReadOnlySpan<char>> span))
		{
			var result = span.TryAdd(key.Text, value);
			key.Clear();
			return result;
		}

		return dictionary.TryAdd(key.ToStringAndClear(), value);
	}

	public static bool ContainsKey<TValue>(this Dictionary<string, TValue> dictionary, ref DefaultInterpolatedStringHandler key)
	{
		if (dictionary.TryGetAlternateLookup(out Dictionary<string, TValue>.AlternateLookup<ReadOnlySpan<char>> span))
		{
			var result = span.ContainsKey(key.Text);
			key.Clear();
			return result;
		}

		return dictionary.ContainsKey(key.ToStringAndClear());
	}

	public static bool Remove<TValue>(this Dictionary<string, TValue> dictionary, ref DefaultInterpolatedStringHandler key)
	{
		if (dictionary.TryGetAlternateLookup(out Dictionary<string, TValue>.AlternateLookup<ReadOnlySpan<char>> span))
		{
			var result = span.Remove(key.Text);
			key.Clear();
			return result;
		}

		return dictionary.Remove(key.ToStringAndClear());
	}
}

API Usage

// Fancy the value
var c = new Dictionary<string, int>();
c.TryAdd($"{something}fancy{thing}",42);

// Getting the values out
c.TryGet($"{11}_{Guid.Empty}", out var value)

//Remove
...

//ContainsKey
....

Alternative Designs

Once DefaultInterpolatedStringHandler exposed Text and Clear, this extension can be build by everybody in his codebase.

Risks

Somebody already defined such extension in his codebase.