Add length to string encoding

[osopardo1]

Description

WIP on #188

Type of change

WIP

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• New feature / bug fix has been committed following the Contribution guide.
• Add comments to the code (make it easier for the community!).
• Change the documentation.
• Add tests.
• Your branch is updated to the main branch (dependent changes have been merged).

How Has This Been Tested? (Optional)

Please describe the tests that you ran to verify your changes.

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• Test B: (e.g., Running some benchmarks...)

Test Configuration:

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[osopardo1]

This is a Draft Pull Request with some structural changes for fixing #188

We incorporate a new Transformation called LengthHashTransformation (feel free to change the name, it was an ugly workaround 😄 ) which will encode the string with a pre-defined length, trying to ensure lexicographic order (very loosely) for hash.

We opened this mainly for @Adricu8 to take over the issue 👏
Good luck!! Let me know if you find any weird behaviour or code block.

[osopardo1]

Closing this PR until clear planning.