Revert "fs: Replace a bunch of uses of smol::fs with manual impls" (#40406)

Reverts zed-industries/zed#40172

crates/fs_benchmarks/src/main.rs

@@ -1,32 +0,0 @@
-use fs::Fs;
-use gpui::{AppContext, Application};
-fn main() {
-    let Some(path_to_read) = std::env::args().nth(1) else {
-        println!("Expected path to read as 1st argument.");
-        return;
-    };
-
-    let _ = Application::headless().run(|cx| {
-        let fs = fs::RealFs::new(None, cx.background_executor().clone());
-        cx.background_spawn(async move {
-            let timer = std::time::Instant::now();
-            let result = fs.load_bytes(path_to_read.as_ref()).await;
-            let elapsed = timer.elapsed();
-            if let Err(e) = result {
-                println!("Failed `load_bytes` after {elapsed:?} with error `{e}`");
-            } else {
-                println!("Took {elapsed:?} to read {} bytes", result.unwrap().len());
-            };
-            let timer = std::time::Instant::now();
-            let result = fs.metadata(path_to_read.as_ref()).await;
-            let elapsed = timer.elapsed();
-            if let Err(e) = result {
-                println!("Failed `metadata` after {elapsed:?} with error `{e}`");
-            } else {
-                println!("Took {elapsed:?} to query metadata");
-            };
-            std::process::exit(0);
-        })
-        .detach();
-    });
-}