[ref] bc-db-writer: rearrangement by storage type (blocks, indexes)

lib/modules-lib/bc-db-reader/src/blocks/fork_tree.rs

lib/modules-lib/bc-db-reader/src/indexes.rs

lib/modules/blockchain/bc-db-writer/src/blocks.rs

lib/modules/blockchain/bc-db-writer/src/blocks/fork_tree.rs

lib/modules/blockchain/bc-db-writer/src/indexes.rs

lib/modules/blockchain/bc-db-writer/src/indexes/certs.rs

lib/modules/blockchain/bc-db-writer/src/indexes/dividends.rs

...modules/blockchain/bc-db-writer/src/indexes/identities.rs

...dules/blockchain/bc-db-writer/src/indexes/transactions.rs

lib/modules/blockchain/bc-db-writer/src/lib.rs

lib/modules/blockchain/bc-db-writer/src/writers/mod.rs

lib/modules/blockchain/bc-db-writer/src/writers/requests.rs

lib/modules/blockchain/blockchain/src/dubp/mod.rs

lib/modules/blockchain/blockchain/src/dunp/receiver.rs

lib/modules/blockchain/blockchain/src/fork/fork_algo.rs

lib/modules/blockchain/blockchain/src/fork/revert_block.rs

lib/modules/blockchain/blockchain/src/fork/rollback.rs

...odules/blockchain/blockchain/src/fork/stackable_blocks.rs

...les/blockchain/blockchain/src/sync/apply/blocks_worker.rs