feat: add language locales

[gnikit]

Is there an existing request for this?

• I have searched the existing issues

Feature Request

• VS Code localisation general resource: https://code.visualstudio.com/docs/getstarted/locales
• VS Code sample extension using localisation: https://github.com/microsoft/vscode-extension-samples/tree/main/i18n-sample
• SO post providing some additional info: https://stackoverflow.com/questions/56420338/how-to-localise-vscode-extension