Remove raft, wal, transactions

Removes raft, transactions, wal and associated helpers, CLI tools with the help of Claude.

In the process since housekeeping's rehydrating and offloading were based on transactions, those features will no longer be supported.

The following were removed:

• Raft: raftmgr/, service/raft/, proto/cluster.proto, raft client helper, raft config
• WAL: storage/wal/, storage/storagemgr/partition/log/, storage/storagemgr/partition/transaction_manager*, WAL backup (internal/backup/log_entry.go), WAL CLI subcommands (cluster_, recovery_, badger_db), partition backup
• Transactions: Transaction interface, ExtractTransaction, PartitionInfo context plumbing, transaction-manager middleware, proc-receive hook + ProcReceiveHook RPC (which only existed to support WAL transactional receives)
• Storage abstractions: Node/Storage/Partition interfaces, databasemgr (badger KV used only by raft/WAL), partition assigner, partition manager

Some feature flags were not removed.

Failing pipeline not from the removal, its another bug in the pipeline.