docs: add CONTRIBUTING.md and LICENSE files

Author: ABGEO

.openapi-generator/FILES

@@ -1,5 +1,7 @@
 .gitignore
 .php-cs-fixer.dist.php
+CONTRIBUTING.md
+LICENSE
 README.md
 composer.json
 docs/Api/SmsApi.md

CONTRIBUTING.md

@@ -0,0 +1,20 @@
+# Contributing
+
+Welcome! This repository contains the **generated SDK** for the ubill.ge API.
+
+⚠️ **Important:** This SDK is generated automatically
+from [ubill-ge/sdk-generator](https://github.com/ubill-ge/sdk-generator),
+which contains the OpenAPI specification, generator config, and templates.
+**Please do not make changes directly in this repository.**
+All manual updates must be made in the `sdk-generator` repo.
+
+## How to Contribute
+
+If you want to contribute:
+
+1. **Open an issue here** to report bugs, suggest improvements, or ask questions.
+2. **Make changes in [`sdk-generator`](https://github.com/ubill-ge/sdk-generator):**
+    - Update the OpenAPI spec (`openapi.yaml`)
+    - Adjust templates or config files
+3. Open a pull request in `sdk-generator`.
+4. Once merged, the SDK will be regenerated and pushed to this repository.

LICENSE

@@ -0,0 +1,21 @@
+MIT License
+
+Copyright (c) 2025-present UBill
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.

README.md

@@ -104,6 +104,15 @@ This PHP package is automatically generated by the [OpenAPI Generator](https://o
     - Generator version: `7.13.0`
 - Build package: `org.openapitools.codegen.languages.PhpClientCodegen`
 
+## Contributing
+
+Please see the [CONTRIBUTING.md](./CONTRIBUTING.md) file for guidelines on how to contribute.
+
 ## Authors
 
 - [Temuri Takalandze](https://www.abgeo.dev) - *Maintainer*
+
+## License
+
+Copyright (c) 2025-present UBill.
+Released under the [MIT](./LICENSE) License.