Implement usage of composer.json instead of iso.txt and others

[Crizz0]

phpBB 4 will use a composer.json instead of lang-key or the iso.txt to gather information about the language package.

• Remove the usage of the iso.txt
• Read the new composer.json from the language packs
• Implement it for:
  • Plural rule
  • ReCaptcha
  • Iso Code
  • Name check
  • version check
  • phpbb version check
  • check for the provided URL
  • check for type
  • check description
  • check license
  • check user lang
  • check turnstile lang
  • check reading direction