feat(pool): add a Cache pooling service

Author: seanmonstar

Cargo.toml

@@ -55,7 +55,7 @@ system-configuration = { version = "0.6.1", optional = true }
 windows-registry = { version = "0.5", optional = true }
 
 [features]
-default = []
+default = ["client", "client-pool"]
 
 # Shorthand to enable everything
 full = [
@@ -76,7 +76,7 @@ full = [
 
 client = ["hyper/client", "tokio/net", "dep:tracing", "dep:futures-channel", "dep:tower-service"]
 client-legacy = ["client", "dep:socket2", "tokio/sync", "dep:libc", "dep:futures-util"]
-client-pool = []
+client-pool = ["dep:futures-util"]
 client-proxy = ["client", "dep:base64", "dep:ipnet", "dep:percent-encoding"]
 client-proxy-system = ["dep:system-configuration", "dep:windows-registry"]