Teku 26.8.0 Drops Legacy Deposit Fetch for EIP-6110

Teku 26.8.0 released with breaking changes and bug fixes. Removes legacy web3j deposit-log fetching; nodes no longer need Eth1 JSON-RPC endpoints, using EIP-6110 instead. Removed validator-tools deposit subcommands and GetDepositSnapshot RPC. Fixed REST socket retention and BeaconBlocksByRange edge case. Archive nodes on leveldb-tree face slow startup.