docs: intial implementation based on rustdoc and mermaid

[FlorianFranzen]

Description

This adds the new documentation-only analog-docs crate to he repo and adds an extended flow documentation to the task pallet.

Type of change

Please delete options that are not relevant.

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• This change requires a documentation update

Code review prechecks:

• [] Code follows the style guidelines of this project
• Code has been self-reviewed
• Inline comments have been added for each method
• I have made corresponding changes to the documentation
• Code changes introduces no new problems or warnings
• [ Test cases have been added
• Dependent changes have been merged and published in downstream modules