Internal connection timeout with low concurrency

I am able to trigger a internal connection timeout easily with even low concurrency on local development machine.

I ran cargo run --release in libsql-server directory and then generated some load with tursotest stress:

go run main.go stress http://localhost:8080 -c 10 -i 1000 -w insert
go run main.go stress http://localhost:8080 -c 10 -i 100000 -w select

which quickly starts to trigger the following:

Welcome to sqld!

version: 0.23.0
commit SHA: e388a72f2d05bd49b6e946d50f94c45f50f2e22e
build date: 2024-03-12

This software is in BETA version.
If you encounter any bug, please open an issue at https://github.com/tursodatabase/libsql/issues

config:
        - mode: standalone
        - database path: data.sqld
        - extensions path: <disabled>
        - listening for HTTP requests on: 127.0.0.1:8080
        - grpc_tls: no
2024-03-12T10:23:00.992876Z  INFO sqld: listening for incoming user HTTP connection on 127.0.0.1:8080
2024-03-12T10:23:01.001489Z  INFO new:restore: libsql_server::namespace::meta_store: restoring meta store
2024-03-12T10:23:01.001532Z  INFO new:restore: libsql_server::namespace::meta_store: meta store restore completed
2024-03-12T10:23:01.004357Z  INFO libsql_server: Server sending heartbeat to URL <not supplied> every 30s
2024-03-12T10:23:01.006199Z  INFO libsql_server::replication::primary::logger: SQLite autocheckpoint: 1000
2024-03-12T10:23:01.010916Z  INFO libsql_server::namespace::store: loaded namespace: `default`
2024-03-12T10:24:41.757702Z ERROR libsql_server::hrana::http: hrana server: Timed out while opening database connection
2024-03-12T10:24:41.757706Z ERROR libsql_server::hrana::http: hrana server: Timed out while opening database connection
2024-03-12T10:24:41.757742Z ERROR libsql_server::hrana::http: hrana server: Timed out while opening database connection
2024-03-12T10:24:41.757768Z ERROR libsql_server::error: HTTP API: 500 Internal Server Error, Anyhow(Timed out while opening database connection)
2024-03-12T10:24:41.757748Z ERROR libsql_server::error: HTTP API: 500 Internal Server Error, Anyhow(Timed out while opening database connection)
2024-03-12T10:24:41.757780Z ERROR libsql_server::error: HTTP API: 500 Internal Server Error, Anyhow(Timed out while opening database connection)
2024-03-12T10:24:41.953718Z ERROR libsql_server::hrana::http: hrana server: Timed out while opening database connection
2024-03-12T10:24:41.953739Z ERROR libsql_server::error: HTTP API: 500 Internal Server Error, Anyhow(Timed out while opening database connection)
2024-03-12T10:24:42.002774Z ERROR libsql_server::hrana::http: hrana server: Timed out while opening database connection
2024-03-12T10:24:42.002796Z ERROR libsql_server::error: HTTP API: 500 Internal Server Error, Anyhow(Timed out while opening database connection)
2024-03-12T10:24:42.083788Z ERROR libsql_server::hrana::http: hrana server: Timed out while opening database connection

Reproduce the timeout from the libsql-server directory with the shown tursotest stress commands and inspect the hrana HTTP connection-opening path, especially the libsql_server::hrana::http errors. Done means the same low-concurrency insert and select workloads no longer produce database-opening timeouts or HTTP 500 responses.