docs(LICENSE): Migrate from CC0 to Land Public License v1.0

Replaced Creative Commons Zero license with custom Land Public License (LPL) v1.0 to establish clear copyleft terms for the Land project. Key changes:
- Introduces strong copyleft provisions requiring LPL-licensed components to remain open
- Defines compatibility rules for combining with External Works while maintaining LPL governance
- Adds patent grants with defensive termination clauses
- Implements attribution requirements and source code distribution obligations
- Establishes Sofia, Bulgaria as jurisdiction for dispute resolution

This aligns with Land's goals to foster open collaboration while protecting against proprietary forks. The LPL ensures contributions remain freely available under reciprocal terms, supporting sustainable ecosystem growth around the Tauri-based editor architecture.

BREAKING CHANGE: Transition from permissive CC0 to copyleft LPL v1.0 significantly alters distribution rights. All future contributions must be licensed under LPL terms.

Author: NikolaRHristov