docs(LICENSE): Switch to CC0 1.0 Universal license

- Replaces custom Land Public License (LPL v1.0) with CC0 public domain dedication
- Removes copyleft requirements and complex license compatibility clauses from LPL
- Aligns with Land project's goal of maximum openness by dedicating work to public domain
- Simplifies third-party contributions by eliminating patent litigation clauses
- Retains only CC0's warranty disclaimer and liability limitations
- Requires no attribution, enabling unrestricted use/modification/distribution
- Impacts all project components by removing previous LPL obligations while maintaining permissive access

Author: NikolaRHristov