refactor: clean repository structure for v0.1.0 open source release

- Remove Go artifacts (cmd/, internal/, pkg/, go.mod)
- Move furt-lua/* content to repository root
- Restructure as clean src/, config/, scripts/, tests/ layout
- Rewrite README.md as practical tool documentation
- Remove timeline references and marketing language
- Clean .gitignore from Go-era artifacts
- Update config/server.lua with example.org defaults
- Add .env.production to .gitignore for security

Repository now ready for open source distribution with minimal,
focused structure and generic configuration templates.
close issue DAW/furt#86

projct-tree.txt

@@ -0,0 +1,38 @@
+.
+├── furt-lua
+│   ├── config
+│   │   └── server.lua
+│   ├── deployment
+│   │   └── openbsd
+│   │       └── rc.d-furt
+│   ├── production_checklist.md
+│   ├── README.md
+│   ├── scripts
+│   │   ├── cleanup_debug.sh
+│   │   ├── manual_mail_test.sh
+│   │   ├── production_test_sequence.sh
+│   │   ├── setup_env.sh
+│   │   ├── start.sh
+│   │   ├── stress_test.sh
+│   │   ├── test_auth.sh
+│   │   ├── test_curl.sh
+│   │   ├── test_modular.sh
+│   │   └── test_smtp.sh
+│   ├── src
+│   │   ├── auth.lua
+│   │   ├── ip_utils.lua
+│   │   ├── main.lua
+│   │   ├── rate_limiter.lua
+│   │   ├── routes
+│   │   │   ├── auth.lua
+│   │   │   └── mail.lua
+│   │   └── smtp.lua
+│   └── tests
+│       └── test_http.lua
+├── LICENSE
+├── projct-tree.txt
+├── README.md
+└── tools
+    └── gitea -> /home/michael/tools/tool-gitea-workflow/scripts
+
+11 directories, 25 files