feat(shell): add interactive line editing history

Cargo.toml

@@ -20,6 +20,11 @@ name              = "kite_sql"
 path              = "src/bin/server.rs"
 required-features = ["net", "rocksdb"]
 
+[[bin]]
+name              = "kitesql-shell"
+path              = "src/bin/shell.rs"
+required-features = ["rocksdb"]
+
 [lib]
 doctest = false
 crate-type = ["cdylib", "rlib"]
@@ -91,6 +96,7 @@ rocksdb = { version = "0.23", optional = true }
 librocksdb-sys = { version = "0.17.1", optional = true }
 lmdb = { version = "0.8.0", optional = true }
 lmdb-sys = { version = "0.8.0", optional = true }
+rustyline = { version = "14", default-features = false }
 
 [target.'cfg(target_arch = "wasm32")'.dependencies]
 wasm-bindgen        = { version = "0.2.106" }

README.md

@@ -145,6 +145,13 @@ fn main() -> Result<(), DatabaseError> {
 On native targets, `LMDB` shines when reads dominate, while `RocksDB` is usually the stronger choice when writes do.
 Checkpoint support and feature-gating details are documented in [docs/features.md](docs/features.md).
 
+## Shell
+- Run `cargo run --bin kitesql-shell` to open the local interactive shell.
+- Use `cargo run --bin kitesql-shell -- --path ./tmp/kitesql-shell-data` to point to a custom RocksDB directory.
+- Use `cargo run --bin kitesql-shell -- -e "select current_timestamp"` for a quick one-shot check.
+- In interactive mode, end SQL statements with `;`; an empty line also executes the buffered statement.
+- Supported metacommands include `.help`, `.quit`, `.tables`, `.views`, and `.schema <name>`.
+
 👉**more examples**
 - [hello_world](examples/hello_world.rs)
 - [transaction](examples/transaction.rs)

docs/features.md

@@ -1,4 +1,34 @@
 ## Features
+### Shell
+
+Run the local interactive shell with:
+
+```bash
+cargo run --bin kitesql-shell
+```
+
+Use a custom data directory:
+
+```bash
+cargo run --bin kitesql-shell -- --path ./tmp/kitesql-shell-data
+```
+
+Run a one-shot SQL check:
+
+```bash
+cargo run --bin kitesql-shell -- -e "select current_timestamp"
+```
+
+In interactive mode, end SQL statements with `;`; an empty line also executes the buffered statement.
+
+Built-in metacommands:
+
+- `.help`
+- `.quit`
+- `.tables`
+- `.views`
+- `.schema <name>`
+
 ### PG Wire: 
 
 run `cargo run --features="net"` to start service