Refactor Fs::watch_file to be more async (#2176)

Refactors Fs::watch_file to use an async notifier rather than the loop-based approach that it previously used. This is more compatible with the new async runtime we're working towards.

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Co-authored-by: Aaron <aaronarinder@gmail.com>

Cargo.toml

@@ -149,6 +149,7 @@ tempfile = "3.8"
 tokio = "1.38"
 tokio-stream = "0.1"
 tokio-test = "0.4.4"
+tokio-util = "0.7.12"
 toml = "0.8"
 tower = { version = "0.5.0", features = ["make", "retry", "timeout"] }
 tower-http = "0.5.2"

crates/rover-std/Cargo.toml

@@ -12,12 +12,16 @@ camino = { workspace = true }
 console = { workspace = true }
 notify = { workspace = true }
 notify-debouncer-full = { workspace = true }
-tokio = { workspace = true }
+tap = { workspace = true }
+tokio = { workspace = true, features = [ "macros", "rt", "rt-multi-thread", "time" ] }
+tokio-util = { workspace = true}
 thiserror = { workspace = true }
 tracing = { workspace = true }
 url = { workspace = true }
 
 [dev-dependencies]
-speculoos = { workspace = true }
+notify = { workspace = true }
+notify-debouncer-full = { workspace = true }
 rstest = { workspace = true }
-tempfile = { workspace = true }
+speculoos = { workspace = true }
+tempfile = { workspace = true }