`libsql::Builder` panics if given invalid remote db url

Builder::new_remote_replica build panics if supplied with an invalid url.

When trying to build an embedded replica of a db with a malformed db url, the build() method just panics and crashes the thread. In my case, I was taking an un-sanitized db name from user as input (stupid of me, I know); create a new namespace in sqld and initialize the user db with that name and then create an embedded synced replica for that db. Surprisingly, sqld successfully creates a namespace even if the name would result in an invalid db_url (maybe I should create another issue for that) and when I try to create the embedded replica with that invalid url it just panics. For example, if the user input is db-name I create a sqld namespace for the same and the sqld instance is available at something like db-name.local which is then synced locally. This works fine as it should. But if the user input is something like db-name:3000, sqld creates a namespace for it even though the url to access this db would be db-name:3000.local which is invalid and embedded replica creation crashes.

The offending line seems to be this:

https://github.com/tursodatabase/libsql/blob/966757ab036e5f787054fdb0f6923c84401f57cd/libsql/src/local/database.rs#L94

Not sure why there is a greedy unwrap here.

Expected: Gracefully error out with an appropriate error.

Start in libsql/src/local/database.rs around line 94 and trace Builder::new_remote_replica through build() for malformed remote database URLs. Confirm how the invalid URL reaches the panic, then make completion return an appropriate error instead; verify that the malformed-url case no longer crashes the thread.