add thai_5000 and thai_lexitron

[longman694]

Description

Add 5000 Thai words (thai_5000.json) and Thai word from LEXiTRON dictionary (thai_lexitron)

Checklist

• I have read the CODE_OF_CONDUCT.md and the CONTRIBUTING.md
• I checked if my PR has any bugs or other issues that could reduce the stability of the project
• I understand that the maintainer has the right to reject my contribution and it may not get accepted.
• If my PR is a new language or theme I modified the appropriate files to incorporate the language or theme