add: TextForge - 28 text transformations via one API - #3

Adds TextForge to the directory.

TextForge provides 28 text transformations through a single API endpoint:

• Case conversion (slugify, camelcase, snakecase, kebabcase, etc.)
• Encoding (base64, HTML, morse, leet)
• Extraction (emails, URLs, numbers)
• Utilities (reverse, truncate, countwords, removespecial)
• Pipelines: chain multiple transforms in one request

Pricing: Free tier (1,000 requests/day, no API key) · Pro .99/mo (50,000/day)

Links:

• Website: https://textforge.co
• Playground: https://textforge.co/playground
• Docs: https://textforge.co/docs
• GitHub: https://github.com/M0N0S0DIUM/Textforge