Extract paths out of util (#13182)

This PR extracts the definition of the various Zed paths out of `util`
and into a new `paths` crate.

`util` is for generic utils, while these paths are Zed-specific. For
instance, `gpui` depends on `util`, and it shouldn't have knowledge of
these paths, since they are only used by Zed.

Release Notes:

- N/A

crates/db/src/db.rs

@@ -7,10 +7,10 @@ use anyhow::Context;
 use gpui::AppContext;
 pub use indoc::indoc;
 pub use lazy_static;
+pub use paths::DB_DIR;
 pub use smol;
 pub use sqlez;
 pub use sqlez_macros;
-pub use util::paths::DB_DIR;
 
 use release_channel::ReleaseChannel;
 pub use release_channel::RELEASE_CHANNEL;