new IR with dependency resolving (#33)

This PR introduces a new internal representation (IR) of the workflow in the `Workflow` class
- The dependencies are resolved.
- The `Store` and `TimeSeries` classes have been introduced to host the cylces, tasks and data with easy access.
- A string representation of the graph is introduced for internal inspection, serving also as serialized data for the CI.

This new IR should facilitate the interface to `aiida-workgraph` and the generation of a visualization graph (#34)

pyproject.toml

@@ -28,7 +28,8 @@ dependencies = [
   "isoduration",
   "pydantic",
   "pydantic-yaml",
-  "aiida-core>=2.5"
+  "aiida-core>=2.5",
+  "termcolor"
 ]
 [project.urls]
 Repository = "https://github.com/C2SM/Sirocco.git"