refactor(tvix/glue): move builtins into separate directory

Change-Id: I25b7197458dbfbde8623545dc0a0286eb2744f10
Reviewed-on: https://cl.tvl.fyi/c/depot/+/9911
Autosubmit: flokli <flokli@flokli.de>
Tested-by: BuildkiteCI
Reviewed-by: raitobezarius <tvl@lahfa.xyz>

tvix/glue/src/errors.rs

@@ -1,26 +0,0 @@
-use nix_compat::{derivation::DerivationError, nixhash};
-use std::rc::Rc;
-use thiserror::Error;
-
-/// Errors related to derivation construction
-#[derive(Debug, Error)]
-pub enum Error {
-    #[error("an output with the name '{0}' is already defined")]
-    DuplicateOutput(String),
-    #[error("fixed-output derivations can only have the default `out`-output")]
-    ConflictingOutputTypes,
-    #[error("the environment variable '{0}' has already been set in this derivation")]
-    DuplicateEnvVar(String),
-    #[error("invalid derivation parameters: {0}")]
-    InvalidDerivation(DerivationError),
-    #[error("invalid output hash: {0}")]
-    InvalidOutputHash(nixhash::Error),
-    #[error("invalid output hash mode: '{0}', only 'recursive' and 'flat` are supported")]
-    InvalidOutputHashMode(String),
-}
-
-impl From<Error> for tvix_eval::ErrorKind {
-    fn from(err: Error) -> Self {
-        tvix_eval::ErrorKind::TvixError(Rc::new(err))
-    }
-}