update action to dagger 0.2

- Remove AGE key setup
- Update README to use `dagger do`
- Update tests to dagger 0.2

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

test/cue.mod/pkg/dagger.io/dagger/fs.cue

@@ -0,0 +1,118 @@
+package dagger
+
+// Access the source directory for the current CUE package
+// This may safely be called from any package
+#Source: {
+	$dagger: task: _name: "Source"
+
+	// Relative path to source.
+	path: string
+	// Optionally exclude certain files
+	include: [...string]
+	// Optionally include certain files
+	exclude: [...string]
+
+	output: #FS
+}
+
+// Create one or multiple directory in a container
+#Mkdir: {
+	$dagger: task: _name: "Mkdir"
+
+	// Container filesystem
+	input: #FS
+
+	// Path of the directory to create
+	// It can be nested (e.g : "/foo" or "/foo/bar")
+	path: string
+
+	// Permissions of the directory
+	permissions: *0o755 | int
+
+	// If set, it creates parents' directory if they do not exist
+	parents: *true | false
+
+	// Modified filesystem
+	output: #FS
+}
+
+#ReadFile: {
+	$dagger: task: _name: "ReadFile"
+
+	// Filesystem tree holding the file
+	input: #FS
+	// Path of the file to read
+	path: string
+	// Contents of the file
+	contents: string
+}
+
+// Write a file to a filesystem tree, creating it if needed
+#WriteFile: {
+	$dagger: task: _name: "WriteFile"
+
+	// Input filesystem tree
+	input: #FS
+	// Path of the file to write
+	path: string
+	// Contents to write
+	contents: string
+	// Permissions of the file
+	permissions: *0o600 | int
+	// Output filesystem tree
+	output: #FS
+}
+
+// Copy files from one FS tree to another
+#Copy: {
+	$dagger: task: _name: "Copy"
+	// Input of the operation
+	input: #FS
+	// Contents to copy
+	contents: #FS
+	// Source path (optional)
+	source: string | *"/"
+	// Destination path (optional)
+	dest: string | *"/"
+	// Output of the operation
+	output: #FS
+}
+
+#CopyInfo: {
+	source: {
+		root: #FS
+		path: string | *"/"
+	}
+	dest: string
+}
+
+// Merge multiple FS trees into one
+#Merge: {
+	@dagger(notimplemented)
+	$dagger: task: _name: "Merge"
+
+	input: #FS
+	layers: [...#CopyInfo]
+	output: #FS
+}
+
+// Select a subdirectory from a filesystem tree
+#Subdir: {
+	// Input tree
+	input: #FS
+
+	// Path of the subdirectory
+	// Example: "/build"
+	path: string
+
+	// Copy action
+	_copy: #Copy & {
+		"input":  #Scratch
+		contents: input
+		source:   path
+		dest:     "/"
+	}
+
+	// Subdirectory tree
+	output: #FS & _copy.output
+}