[CRAN feedback] Revise DESCRIPTION field per CRAN requirements

[villegar]

Summary:

• Update the DESCRIPTION field to satisfy CRAN requirements. The description should not start with the package name, "This package", or similar. It must concisely and informatively describe what the package does and why it is useful, referencing implemented methods or functionality where helpful.

Current DESCRIPTION:

Description: R package to wrap elements from 'DataSHIELD' analysis into an 
    RO-Crate.

CRAN Feedback:

• Do not start with "This package", package name, title, etc.
• Provide a richer, single-paragraph description, with details on what is implemented and why it is useful.

Reference/Link:

• CRAN Cookbook: Description field

Checklist:

• Rewrite DESCRIPTION as requested
• Ensure description length and informativeness meet guidance
• Confirm no forbidden opening phrases
• Update in NAMESPACE if necessary