cue modules: move stdlib to pkg/alpha.dagger.io

In preparation for Europa, we will vendor multiple CUE modules:

- `pkg/alpha.dagger.io`: legacy non-europa packages
- `pkg/dagger.io`: core Europa packages
- `pkg/universe.dagger.io`: Europa universe

Signed-off-by: Andrea Luzzardi <aluzzardi@gmail.com>

pkg/alpha.dagger.io/docker/tests/run-local/local.cue

@@ -0,0 +1,18 @@
+package docker
+
+import (
+	"alpha.dagger.io/dagger"
+	"alpha.dagger.io/random"
+)
+
+dockersocket: dagger.#Stream & dagger.#Input
+
+suffix: random.#String & {
+	seed: ""
+}
+
+run: #Run & {
+	name:   "daggerci-test-local-\(suffix.out)"
+	ref:    "hello-world"
+	socket: dockersocket
+}