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/js/yarn/tests/testdata/package.json

@@ -0,0 +1,11 @@
+{
+  "name": "test",
+  "main": "index.js",
+  "license": {
+    "type": "Apache-2.0",
+    "url": "https://opensource.org/licenses/apache2.0.php"
+  },
+  "scripts": {
+	  "build": "mkdir -p ./build && echo output > ./build/test && touch .env && cp .env ./build/"
+  }
+}

pkg/alpha.dagger.io/js/yarn/tests/testdata2/package.json

@@ -0,0 +1,12 @@
+{
+	"name": "test",
+	"main": "index.js",
+	"license": {
+	  "type": "Apache-2.0",
+	  "url": "https://opensource.org/licenses/apache2.0.php"
+	},
+	"scripts": {
+		"build": "mkdir -p ./build && cp /.env ./build/env"
+	}
+  }
+  

pkg/alpha.dagger.io/js/yarn/tests/yarn.cue

@@ -0,0 +1,57 @@
+package yarn
+
+import (
+	"alpha.dagger.io/dagger"
+	"alpha.dagger.io/alpine"
+	"alpha.dagger.io/os"
+)
+
+TestData: dagger.#Artifact
+
+TestReact: {
+	pkg: #Package & {
+		source: TestData
+	}
+
+	test: os.#Container & {
+		image: alpine.#Image & {
+			package: bash: true
+		}
+		mount: "/build": from: pkg.build
+		command: """
+			test "$(cat /build/test)" = "output"
+			"""
+	}
+}
+
+TestData2: dagger.#Artifact
+
+TestSecretsAndFile: {
+	pkg: #Package & {
+		source:       TestData2
+		writeEnvFile: "/.env"
+		env: {
+			one: "one"
+			two: "two"
+		}
+		secrets: {
+			secretone: dagger.#Secret @dagger(input)
+			secretwo:  dagger.#Secret @dagger(input)
+		}
+	}
+
+	test: os.#Container & {
+		image: alpine.#Image & {
+			package: bash: true
+		}
+		shell: path: "/bin/bash"
+		mount: "/build": from: pkg.build
+		command: """
+			content="$(cat /build/env)"
+			[[ "${content}" = *"SECRETONE="* ]] && \\
+			[[ "${content}" = *"SECRETWO="* ]] && \\
+			[[ "${content}" = *"ONE=one"* ]] && \\
+			[[ "${content}" = *"TWO=two"* ]]
+			"""
+	}
+}