null pointer while sync from remote

I'm using sqld docker as the remote server and using remote_replica. Got this error.

let db = libsql::Builder::new_remote_replica(
        db_path,
        url,
        token,
    )
    .build()
    .await
    .expect("fail to build DB");
 db.sync().await

thread 'tokio-runtime-worker' panicked at /Users/username/.cargo/registry/src/index.crates.io-1949cf8c6b5b557f/libsql-sys-0.9.7/src/wal/ffi.rs:449:59:
null pointer dereference occurred
stack backtrace:
   0: rust_begin_unwind
             at /rustc/05f9846f893b09a1be1fc8560e33fc3c815cfecb/library/std/src/panicking.rs:695:5
   1: core::panicking::panic_nounwind_fmt::runtime
             at /rustc/05f9846f893b09a1be1fc8560e33fc3c815cfecb/library/core/src/panicking.rs:117:22
   2: core::panicking::panic_nounwind_fmt
             at /rustc/05f9846f893b09a1be1fc8560e33fc3c815cfecb/library/core/src/intrinsics/mod.rs:3886:9
   3: core::panicking::panic_null_pointer_dereference
             at /rustc/05f9846f893b09a1be1fc8560e33fc3c815cfecb/library/core/src/panicking.rs:304:5
   4: libsql_sys::wal::ffi::checkpoint
             at /Users/username/.cargo/registry/src/index.crates.io-1949cf8c6b5b557f/libsql-sys-0.9.7/src/wal/ffi.rs:449:59
   5: sqlite3PagerCheckpoint
             at /Users/username/.cargo/registry/src/index.crates.io-1949cf8c6b5b557f/libsql-ffi-0.9.7/bundled/src/sqlite3.c:65110:10
   6: sqlite3BtreeCheckpoint
             at /Users/username/.cargo/registry/src/index.crates.io-1949cf8c6b5b557f/libsql-ffi-0.9.7/bundled/src/sqlite3.c:82419:12
   7: sqlite3Checkpoint
             at /Users/username/.cargo/registry/src/index.crates.io-1949cf8c6b5b557f/libsql-ffi-0.9.7/bundled/src/sqlite3.c:183635:12
   8: sqlite3_wal_checkpoint_v2
             at /Users/username/.cargo/registry/src/index.crates.io-1949cf8c6b5b557f/libsql-ffi-0.9.7/bundled/src/sqlite3.c:183573:10
   9: sqlite3_wal_checkpoint
             at /Users/username/.cargo/registry/src/index.crates.io-1949cf8c6b5b557f/libsql-ffi-0.9.7/bundled/src/sqlite3.c:183598:10
  10: sqlite3WalDefaultHook
             at /Users/username/.cargo/registry/src/index.crates.io-1949cf8c6b5b557f/libsql-ffi-0.9.7/bundled/src/sqlite3.c:183464:5
  11: doWalCallbacks
             at /Users/username/.cargo/registry/src/index.crates.io-1949cf8c6b5b557f/libsql-ffi-0.9.7/bundled/src/sqlite3.c:92182:14
  12: sqlite3Step
             at /Users/username/.cargo/registry/src/index.crates.io-1949cf8c6b5b557f/libsql-ffi-0.9.7/bundled/src/sqlite3.c:92309:15
  13: sqlite3_step
             at /Users/username/.cargo/registry/src/index.crates.io-1949cf8c6b5b557f/libsql-ffi-0.9.7/bundled/src/sqlite3.c:92371:16
  14: rusqlite::raw_statement::RawStatement::step
             at /Users/username/.cargo/registry/src/index.crates.io-1949cf8c6b5b557f/libsql-rusqlite-0.9.7/src/raw_statement.rs:106:18
  15: rusqlite::statement::Statement::execute_with_bound_parameters
             at /Users/username/.cargo/registry/src/index.crates.io-1949cf8c6b5b557f/libsql-rusqlite-0.9.7/src/statement.rs:648:17
  16: rusqlite::statement::Statement::execute
             at /Users/username/.cargo/registry/src/index.crates.io-1949cf8c6b5b557f/libsql-rusqlite-0.9.7/src/statement.rs:114:9
  17: libsql_replication::injector::sqlite_injector::SqliteInjectorInner::try_flush
             at /Users/username/.cargo/registry/src/index.crates.io-1949cf8c6b5b557f/libsql_replication-0.9.7/src/injector/sqlite_injector/mod.rs:203:33
  18: libsql_replication::injector::sqlite_injector::SqliteInjectorInner::flush
             at /Users/username/.cargo/registry/src/index.crates.io-1949cf8c6b5b557f/libsql_replication-0.9.7/src/injector/sqlite_injector/mod.rs:153:15
  19: libsql_replication::injector::sqlite_injector::SqliteInjectorInner::inject_frame
             at /Users/username/.cargo/registry/src/index.crates.io-1949cf8c6b5b557f/libsql_replication-0.9.7/src/injector/sqlite_injector/mod.rs:135:20
  20: <libsql_replication::injector::sqlite_injector::SqliteInjector as libsql_replication::injector::Injector>::inject_frame::{{closure}}::{{closure}}
             at /Users/username/.cargo/registry/src/index.crates.io-1949cf8c6b5b557f/libsql_replication-0.9.7/src/injector/sqlite_injector/mod.rs:33:32
  21: <tokio::runtime::blocking::task::BlockingTask<T> as core::future::future::Future>::poll
             at /Users/username/.cargo/registry/src/index.crates.io-1949cf8c6b5b557f/tokio-1.45.0/src/runtime/blocking/task.rs:42:21
  22: tokio::runtime::task::core::Core<T,S>::poll::{{closure}}
             at /Users/username/.cargo/registry/src/index.crates.io-1949cf8c6b5b557f/tokio-1.45.0/src/runtime/task/core.rs:331:17
  23: tokio::loom::std::unsafe_cell::UnsafeCell<T>::with_mut
             at /Users/username/.cargo/registry/src/index.crates.io-1949cf8c6b5b557f/tokio-1.45.0/src/loom/std/unsafe_cell.rs:16:9
  24: tokio::runtime::task::core::Core<T,S>::poll
             at /Users/username/.cargo/registry/src/index.crates.io-1949cf8c6b5b557f/tokio-1.45.0/src/runtime/task/core.rs:320:13
  25: tokio::runtime::task::harness::poll_future::{{closure}}
             at /Users/username/.cargo/registry/src/index.crates.io-1949cf8c6b5b557f/tokio-1.45.0/src/runtime/task/harness.rs:532:19
  26: <core::panic::unwind_safe::AssertUnwindSafe<F> as core::ops::function::FnOnce<()>>::call_once
             at /Users/username/.rustup/toolchains/stable-aarch64-apple-darwin/lib/rustlib/src/rust/library/core/src/panic/unwind_safe.rs:272:9
  27: std::panicking::try::do_call
             at /Users/username/.rustup/toolchains/stable-aarch64-apple-darwin/lib/rustlib/src/rust/library/std/src/panicking.rs:587:40
  28: ___rust_try
  29: std::panicking::try
             at /Users/username/.rustup/toolchains/stable-aarch64-apple-darwin/lib/rustlib/src/rust/library/std/src/panicking.rs:550:19
  30: std::panic::catch_unwind
             at /Users/username/.rustup/toolchains/stable-aarch64-apple-darwin/lib/rustlib/src/rust/library/std/src/panic.rs:358:14
  31: tokio::runtime::task::harness::poll_future
             at /Users/username/.cargo/registry/src/index.crates.io-1949cf8c6b5b557f/tokio-1.45.0/src/runtime/task/harness.rs:520:18
  32: tokio::runtime::task::harness::Harness<T,S>::poll_inner
             at /Users/username/.cargo/registry/src/index.crates.io-1949cf8c6b5b557f/tokio-1.45.0/src/runtime/task/harness.rs:209:27
  33: tokio::runtime::task::harness::Harness<T,S>::poll
             at /Users/username/.cargo/registry/src/index.crates.io-1949cf8c6b5b557f/tokio-1.45.0/src/runtime/task/harness.rs:154:15
  34: tokio::runtime::task::raw::poll
             at /Users/username/.cargo/registry/src/index.crates.io-1949cf8c6b5b557f/tokio-1.45.0/src/runtime/task/raw.rs:271:5
  35: tokio::runtime::task::raw::RawTask::poll
             at /Users/username/.cargo/registry/src/index.crates.io-1949cf8c6b5b557f/tokio-1.45.0/src/runtime/task/raw.rs:201:18
  36: tokio::runtime::task::UnownedTask<S>::run
             at /Users/username/.cargo/registry/src/index.crates.io-1949cf8c6b5b557f/tokio-1.45.0/src/runtime/task/mod.rs:500:9
  37: tokio::runtime::blocking::pool::Task::run
             at /Users/username/.cargo/registry/src/index.crates.io-1949cf8c6b5b557f/tokio-1.45.0/src/runtime/blocking/pool.rs:161:9
  38: tokio::runtime::blocking::pool::Inner::run
             at /Users/username/.cargo/registry/src/index.crates.io-1949cf8c6b5b557f/tokio-1.45.0/src/runtime/blocking/pool.rs:511:17
  39: tokio::runtime::blocking::pool::Spawner::spawn_thread::{{closure}}
             at /Users/username/.cargo/registry/src/index.crates.io-1949cf8c6b5b557f/tokio-1.45.0/src/runtime/blocking/pool.rs:469:13
note: Some details are omitted, run with `RUST_BACKTRACE=full` for a verbose backtrace.
thread caused non-unwinding panic. aborting.

Start by reproducing the remote-replica sync with sqld using the issue's Builder example, then inspect libsql-sys/src/wal/ffi.rs at checkpoint and libsql_replication/src/injector/sqlite_injector/mod.rs around flush and try_flush. Done means sync no longer aborts on the null pointer and the regression is covered by an appropriate test.