Initial vendor packages

Signed-off-by: Valentin Popov <valentin@popov.link>

vendor/thiserror/tests/ui/source-enum-not-error.stderr

@@ -0,0 +1,22 @@
+error[E0599]: the method `as_dyn_error` exists for reference `&NotError`, but its trait bounds were not satisfied
+ --> tests/ui/source-enum-not-error.rs:9:14
+  |
+4 | pub struct NotError;
+  | -------------------
+  | |
+  | doesn't satisfy `NotError: AsDynError<'_>`
+  | doesn't satisfy `NotError: std::error::Error`
+...
+9 |     Broken { source: NotError },
+  |              ^^^^^^ method cannot be called on `&NotError` due to unsatisfied trait bounds
+  |
+  = note: the following trait bounds were not satisfied:
+          `NotError: std::error::Error`
+          which is required by `NotError: AsDynError<'_>`
+          `&NotError: std::error::Error`
+          which is required by `&NotError: AsDynError<'_>`
+note: the trait `std::error::Error` must be implemented
+ --> $RUST/core/src/error.rs
+  |
+  | pub trait Error: Debug + Display {
+  | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^