/auto (#16696)

Add `/auto` behind a feature flag that's disabled for now, even for
staff.

We've decided on a different design for context inference, but there are
parts of /auto that will be useful for that, so we want them in the code
base even if they're unused for now.

Release Notes:

- N/A

---------

Co-authored-by: Antonio Scandurra <me@as-cii.com>
Co-authored-by: Marshall Bowers <elliott.codes@gmail.com>

crates/git/src/status.rs

@@ -57,7 +57,6 @@ impl GitStatus {
             let stderr = String::from_utf8_lossy(&output.stderr);
             return Err(anyhow!("git status process failed: {}", stderr));
         }
-
         let stdout = String::from_utf8_lossy(&output.stdout);
         let mut entries = stdout
             .split('\0')