new parameters added to the trimming commands

[matbonfanti]

This PR implements a new feature I requested in issue #231, introducing parameters that allow specifying additional arguments for the cutadapt command line.

Two separate parameters are provided: one for 5' trimming and one for 3' trimming, as trimming requirements for each read end may vary depending on the experimental setup.

Marking this PR as draft, as further work is needed to:

• Test the implementation
• Update the parameter schema

PR checklist

• This comment contains a description of changes (with reason).
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