feat: add cssStyler option to use typed CSSStyleDeclaration props

[ghiscoding]

deprecate styler in favor of a new cssStyler which have better typing support and can use direct assignment. The previous use of innerHTML made it easier to use styler but now that we switched to pure HTML Element, it is better to use CSSStyleDeclaration props. Since we moved to pure HTML Element, the styler is requiring a bit more logic, since we now have to do string split of semicolon ;, then use toCamelCase for CSS assignment... which is why the new cssStyler is better since we can simply loop through all styling props and assign directly

Styler (deprecated)

styler: (row: OptionRowData | OptGroupRowData) => {
      if (row?.type === 'optgroup') {
          return 'color: #777; font-weight: normal;';
      }
}

CssStyler (new)

styler: (row: OptionRowData | OptGroupRowData) => {
      if (row?.type === 'optgroup') {
          return { backgroundColor: '#972727', color: '#fff' } as CSSStyleDeclaration;
      }
}

[github-actions]

🎭 Playwright Summary - Success 🎉

Playwright Report

[email protected] test:e2e /home/runner/work/multiple-select-vanilla/multiple-select-vanilla
playwright test --config playwright/playwright.config.ts

Running 67 tests using 1 worker
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67 passed (2.4m)