The primary purpose of the CoTA global registry is to make every address mapping only one CoTA cell to avoid the double-claim problem.
The kernel data encoded in the global registry cell is an SMT root for registered addresses, and every address can register once and only once. We also introduce an auto-incremental ID (CoTA Cell ID, aka. CCID) to identify the recorded cells.
To keep the update to the registry cell decentralized enough, its lock script must open to everyone. So we set its lockscript
always_success. Also, you can never create a CoTA cell without registering it to the global registry.
# global_cota_registry_cell data structure