feat(tvix/cli): add errors module with drv construction errors

These will be threaded through to eval through the new `TvixError`
variant.

Change-Id: Ia0d3f8710dcf26bb95015cd2a6a2b2911f06343f
Reviewed-on: https://cl.tvl.fyi/c/depot/+/7842
Reviewed-by: flokli <flokli@flokli.de>
Tested-by: BuildkiteCI

tvix/cli/Cargo.toml

@@ -9,6 +9,7 @@ path = "src/main.rs"
 
 [dependencies]
 tvix-eval = { path = "../eval" }
+tvix-derivation = { path = "../derivation" }
 rustyline = "10.0.0"
 clap = { version = "4.0", features = ["derive", "env"] }
 dirs = "4.0.0"