Support TLS with valkeys:// connection string

[joksnet]

First small step.

[mcollina]

Thanks for opening a PR! Can you please add a unit test?

[mcollina]

Are you still interested in updating this PR? If so, please rebase it onto the current main and add the requested URL parsing tests. The update should handle both valkey:// and valkeys:// consistently, including credentials, ports, trailing slashes, and database paths such as /4; changing only TLS detection leaves database paths parsed as Unix socket paths.

[mcollina]

I have opened #74 with complete valkey:// and valkeys:// parsing, TLS handling, database-path support, and regression tests. It incorporates the change proposed here along with the additional parser work and coverage requested in review, so this PR is now superseded.