feat(ariadne): add CLI skeleton

src/ariadne/BUILD

@@ -3,13 +3,19 @@ load("@rules_rust//rust:defs.bzl", "rust_binary", "rust_library")
 rust_library(
     name = "ariadne_lib",
     crate_name = "ariadne",
-    srcs = ["src/lib.rs"],
+    srcs = [
+        "lib.rs",
+        "pipeline.rs",
+    ],
 )
 
 rust_binary(
     name = "ariadne",
     crate_name = "ariadne_cli",
-    srcs = ["src/main.rs"],
-    deps = [":ariadne_lib"],
+    srcs = ["main.rs"],
+    deps = [
+        ":ariadne_lib",
+        "//third_party/crates:clap",
+    ],
 )