Improvement: How to fix i18n definition in lifecycle handlers

[Flanker72]

Hi! Can't create PR, cause push is not allowed :(

So, please, check this code snippet (only changed lines attached):

// In types.ts
export type I18nThis = Service<{ i18n: I18NSettings }> & ServiceMethods;

// In index.ts
// ...
  async started() {
    const _this = this as unknown as I18nThis // This is the working solution without warnings

    const files = await readFilesSync(_this.settings.i18n.dirName) // Use _this instead of this

    for (const translation of files) {
      // ...
      _this.settings.i18n.polyglot.extend(object) // Use _this instead of this
    }
  }

This reassignment through the unknown allows to use your typed service schema with settings, methods, etc. inside lifecycle handlers like created, started, etc.