Enable "Trigger Parameter Hints" for available method/constructor overloads

Prerequisites

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Summary

Today, available method/constructor overloads are shown when you get to the method body or an open parens

However, if you are already in a closed parens and want to see the available method/constructor overloads, this is not available, you have to delete the closed parens and retype them to get the prompt again.

Proposed Design

The C# extension wires up to Trigger Parameter Hints when in the method/constructor parameter body, we should do the same.

まず、VS Code PowerShell extension における既存のメソッド/コンストラクターのパラメーターヒント処理を見つけ、C# extension の Trigger Parameter Hints への接続方法と比較します。閉じたパラメーターリスト内での動作を確認してください。そこでは、閉じ括弧を削除して再入力しなくても、利用可能なオーバーロードが表示されるはずです。