Fix RTL styling on WordPress Core components

[bcotrim]

Related issues

• Fixes STU-885

Proposed Changes

• Created WordPressStyles component using DynamicStylesheet to dynamically load WordPress component styles based on RTL/LTR direction
• Updated DynamicStylesheet to insert styles at the beginning of head for proper CSS loading order
• Fixed production CSS file paths to use relative paths from renderer HTML
• Removed static WordPress CSS import from index.css in favor of dynamic loading

Testing Instructions

• Run npm start
• Switch language to RTL in settings
• Verify WordPress components (modals, checkboxes) display correctly in RTL
• Test in production build: Run npm run make and verify styles load correctly

Pre-merge Checklist

• Have you checked for TypeScript, React or other console errors?

[github-actions]

📊 Performance Test Results

Comparing b3678f4 vs trunk

site-editor

Metric	trunk	b3678f4	Diff	Change
load	10907.00 ms	9529.00 ms	-1378.00 ms	🟢 -12.6%

site-startup

Metric	trunk	b3678f4	Diff	Change
siteCreation	15090.00 ms	15100.00 ms	+10.00 ms	🔴 0.1%
siteStartup	4964.00 ms	4936.00 ms	-28.00 ms	🟢 -0.6%

---

Results are median values from multiple test runs.

Legend: 🟢 Improvement (faster) | 🔴 Regression (slower) | ⚪ No change

[ivan-ottinger]

Thank you for fixing the issue with the broken RTL styles, Bernardo.

The proposed code looks good to me and works correctly. When a RTL local is set, the related WordPress Core components styles are being loaded as expected.

I have tested it in the dev and also built app.

The paddings around X button in the modal and around checkboxes is now correct.

Just the unit tests need adjustment.

[epeicher]

Thanks @bcotrim for solving this! I have tested it in dev and production mode and it works as expected. I left a minor non-blocking comment. Code also LGTM!

[epeicher]

Nit: Should we apply the same logic for RTL for the errors than here https://github.com/Automattic/studio/pull/1998/files#diff-d47d7dfb85379fc920c32c6ccd0a9f5817e5104a1db25afd75a39b779fc5af70R22 ? 🤔 This is what I get

[bcotrim]

Nice catch! Addressed in dbd0a59

[katinthehatsite]

This works for me, I did not spot any regressions on my end 👌

[sejas]

Nice! Thanks for fixing the RTL CSS issue! ✨