feat: add method - detect format / data_type

[cachho]

Description

Automatically detect and use the data_type in add method.

• a quite sophisticated system to detect the data_type (checks if it's a url, string, local file and then the file extension)
• added tons of unit tests
• documentation changes

breaking change because the first argument of add is now the source/content, not the data type.

Changes the order of arguments, because ``

Fixes #168 #76

Type of change

Please delete options that are not relevant.

• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• Documentation update

How Has This Been Tested?

Please describe the tests that you ran to verify your changes. Provide instructions so we can reproduce. Please also list any relevant details for your test configuration

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• Unit Test

Checklist:

• My code follows the style guidelines of this project
• I have performed a self-review of my own code
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation
• My changes generate no new warnings
• I have added tests that prove my fix is effective or that my feature works
• New and existing unit tests pass locally with my changes
• Any dependent changes have been merged and published in downstream modules
• I have checked my code and corrected any misspellings

Maintainer Checklist

• closes #xxxx (Replace xxxx with the GitHub issue number)
• Made sure Checks passed

[cachho]

New update uses a DataType model. This increases type safety and makes it possible to list the accepted data_types.

[taranjeet]

we should append the Successfully saved https://nav.al/agi. New chunks count print statement. We should show the data type deduced here, so that everyone has visibility of the data type and can corrections if needed.

I know about the logging part, but a lot of users might not use logging. Hence the ask

[cachho]

Good idea

about the logging: warning and above are displayed by default. lower has to be enabled.