Reduce a number of scripts that implement Sandbox CLI

[minherz]

Description

Consolidate CLI implementation inside two scripts

• sandboxctl (Python)
• install.sh (Bash)

Host the scripts in the (new) /cli folder. The script execution logic that is based on the relative location of the scripts should be adjusted accordingly.
Call Bash script from Python script for executing "create" and "delete" operations.
Migrate all implementations of "recipes" operations into Python script.
Implement telemetry for "create" and "delete" operations in the Bash script using gcloud pubsub CLI.
Implement telemetry for "recipes" operations in Python script using gcloud pubsub CLI.

Keep Python required packages to minimum.
Update markdown documentation to reflect how Sandbox can be installed.

Warning
This feature breaks "one-click" deployment because it requires
installing Python dependencies and running sandboxctl as two
separate commands.