refactor : declare and initialize class property

[DongjaJ]

Description

[ What changed? Feel free to be brief. ]

Typescript class grammar allows the constructor to declare and initialize properties at the same time.

I applied it to continue in this PR

And I want to ask you one thing.

If you look at the second commit of this PR, there are properties that have public access designators. Shouldn't these properties be designated as private access designators?

Checklist

• The base branch of this PR is dev, rather than main
• The relevant docs, if any, have been updated or created

Screenshots

[ For visual changes, include screenshots. ]

Testing

[ For new or modified features, provide step-by-step testing instructions to validate the intended behavior of the change. ]

[sestinj]

This is great! Yes, it looks like those public properties in the second commit should all be private

[DongjaJ]

I modified the access designator from public to private