refactor: replace fjall with parity-db (0.5.4)

- Removed `fjall` dependency and backend implementation.
- Restored and updated `parity_backend.rs` to support new `Engine` traits (no return values, `write_batch`).
- Updated `Cargo.toml` files to use `parity-db = 0.5.4`.
- Updated features and README to reflect the change.
- Optimized `ParityEngine` with `make_full_key` and `alloc_prefix` optimizations.
- Verified with `make lint` and `make lintall`.

Author: wlqm

Cargo.toml

@@ -22,7 +22,7 @@ sha3 = "0.10"
 
 threadpool = "1.8.1" # used in a background cleaner
 
-fjall = { version = "2.11.2", default-features = false, features = ["single_writer_tx"] }
+parity-db = { version = "0.5.4" }
 rocksdb = { version = "0.24.0", default-features = false, features = ["bindgen-runtime"] }
 
 vsdb = { path = "wrappers", version = "7.1.0", default-features = false }

Makefile

@@ -14,7 +14,7 @@ lintall: lint
 lintmusl:
 	cargo clippy --workspace --target x86_64-unknown-linux-musl \
 		--no-default-features \
-		--features "fjall_backend,cbor_codec"
+		--features "parity_backend,cbor_codec"
 
 test:
 	- rm -rf ~/.vsdb /tmp/.vsdb /tmp/vsdb_testing $(VSDB_BASE_DIR)
@@ -33,7 +33,7 @@ testmusl:
 	- rm -rf ~/.vsdb /tmp/.vsdb /tmp/vsdb_testing $(VSDB_BASE_DIR)
 	cargo test --workspace --target x86_64-unknown-linux-musl --release --tests \
 		--no-default-features \
-		--features "fjall_backend,cbor_codec" \
+		--features "parity_backend,cbor_codec" \
 		-- --test-threads=1 #--nocapture
 
 bench:
@@ -55,7 +55,7 @@ bench_rocksdb:
 benchmusl:
 	- rm -rf ~/.vsdb /tmp/.vsdb /tmp/vsdb_testing $(VSDB_BASE_DIR)
 	cargo bench --workspace --target x86_64-unknown-linux-musl \
-		--no-default-features --features "fjall_backend,cbor_codec"
+		--no-default-features --features "parity_backend,cbor_codec"
 	du -sh ~/.vsdb
 
 fmt:

core/Cargo.toml

@@ -18,7 +18,7 @@ parking_lot = { workspace = true }
 
 threadpool = { workspace = true } # used in a background cleaner
 
-fjall = { workspace = true, optional = true }
+parity-db = { workspace = true, optional = true }
 rocksdb = { workspace = true, optional = true }
 
 [dev-dependencies]
@@ -27,12 +27,12 @@ hex = "0.4"
 criterion = "0.8"
 
 [features]
-default = ["compress", "fjall_backend"]
+default = ["compress", "parity_backend"]
 
-fjall_backend = ["fjall"]
+parity_backend = ["parity-db"]
 rocks_backend = ["rocksdb"]
 
-compress = ["rocksdb?/zstd", "fjall?/lz4"]
+compress = ["rocksdb?/zstd"]
 
 # [[bench]]
 # name = "basic"