feat: initial commit for regex-humanizer-cli

- Add regex parser, translator, and test generator
- Add CLI with explain, test, interactive commands
- Add multi-flavor support (PCRE, JavaScript, Python)
- Add Gitea Actions CI workflow
- Add comprehensive README documentation

requirements.txt

@@ -0,0 +1,5 @@
+click>=8.0
+regex>=2023.0
+parsimonious>=0.10.0
+pytest>=7.0
+pygments>=2.15