chore: remove triedb (rust-eth-triedb/pathdb) state backend (#371)

* chore: reth dep (#366)

Co-authored-by: joey <10592664+joey0612@users.noreply.github.com>
Co-authored-by: cbh876 <3930922419@qq.com>
Co-authored-by: cbh876 <30834644+constbh@users.noreply.github.com>

* chore: remove triedb (rust-eth-triedb/pathdb) state backend

Drops all triedb code paths and the four rust-eth-triedb* git deps so the
downstream reth-bsc crate compiles against the upstream Reth tree where
PR bnb-chain/reth#202 has removed the same backend. After this change
the only state backend is MDBX.

Pinned `bnb-chain/reth` to rev 6dcb09c0090e046eea6440fbeb58cce5db0476b2
(PR 202 head) and aligned the bsc-ef-tests crate to the same rev.

- evm/builder.rs: collapsed `is_triedb_active()` + finish_with_difflayer
  override into `fn finish`, keeping the sparse-trie precomputed-root
  fast path and the MDBX `state_root_with_updates` fallback. Removed
  the `request_difflayer` helper.
- evm/{mod,config}.rs: removed `MinerTrieDbPrefetcher` type alias,
  `parent_difflayers` / `triedb_prefetcher` fields on
  `BscNextBlockEnvAttributes` + `BscBlockExecutionCtx`, and the
  `create_block_builder` workaround that scrubbed them.
- engine.rs: dropped the `!is_triedb_active()` gate on the sparse-trie
  spawner; `BscBuiltPayload::executed_block` no longer carries a
  difflayer (upstream `ExecutedBlock.difflayer` field deleted).
- miner/payload.rs: removed `parent_difflayers` from
  `BscBuildArguments`, the `fetch_triedb_difflayers` helper, the
  prefetcher state-hook closures, the pathdb safety guard, and the
  `executed_block.difflayer` assignments.
- miner/bid_simulator.rs: removed the triedb branch from
  `bid_simulate` and its `parent_difflayers` parameter.
- miner/bsc_miner.rs: deleted `fetch_parent_difflayers_for_bid` and
  its caller.
- Removed the now-unused `task_executor` field from
  `BscPayloadBuilder`, `BidSimulator`, and `MainWorkWorker` (it
  existed only to spawn the triedb prefetcher).
- README.md / CLAUDE.md / main.rs / miner/config.rs: purged
  `--statedb.triedb` references.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

---------

Co-authored-by: const <122766871+constwz@users.noreply.github.com>
Co-authored-by: joey <10592664+joey0612@users.noreply.github.com>
Co-authored-by: cbh876 <3930922419@qq.com>
Co-authored-by: cbh876 <30834644+constbh@users.noreply.github.com>
Co-authored-by: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

Author: 6 people

CLAUDE.md

@@ -8,7 +8,6 @@ This file provides guidance to Claude Code (claude.ai/code) when working with co
 
 - Workspace members: the root crate (binary `reth-bsc`, library `reth_bsc`) and `testing/bsc-ef-tests` (execution-spec tests harness).
 - All `reth-*` deps are pinned to one commit in `Cargo.toml` (currently `bnb-chain/reth` rev `ef46a48…`). If you change the Reth rev, update **every** `reth-*` line — a mismatched rev produces duplicate-crate build failures. The `testing/bsc-ef-tests/Cargo.toml` uses `branch = "develop"` of the same fork; that's intentional but keep it aligned when bumping.
-- Triedb backend (`--statedb.triedb`) pulls `rust-eth-triedb*` from `bnb-chain/reth-bsc-triedb` on the `develop` branch.
 - `build.rs` scans `src/system_contracts/<hardfork>/{mainnet,chapel,rialto}/*` at build time and emits `src/system_contracts/embedded_contracts.rs` (a `phf_map` keyed as `"<hardfork>_<network>_<contract>"`). It also records the git SHA into `RETH_BSC_GIT_SHA` / `RETH_BSC_GIT_SHA_LONG` used at startup and in the P2P client string. If you add a new hardfork directory with system contracts, add it to the `hardforks` list in `build.rs` so cargo rebuilds when those files change.
 
 ## Common commands
@@ -46,11 +45,10 @@ make ef-tests-nextest   # same, via cargo-nextest
 make clean-eest
 ```
 
-Run (binary is `reth-bsc`, chain ids `bsc`, `bsc-testnet`; optional `--statedb.triedb`):
+Run (binary is `reth-bsc`, chain ids `bsc`, `bsc-testnet`):
 ```bash
 ./target/release/reth-bsc node --chain bsc --datadir ./data_dir
 ./target/release/reth-bsc node --full --chain bsc --datadir ./data_dir            # full node
-./target/release/reth-bsc node --chain bsc --datadir ./data_dir --statedb.triedb  # triedb backend
 ```
 
 ## Where the wiring lives