Added method "show" to medunda main script

[spiani]

No description provided.

[Copilot]

Pull request overview

This PR adds a new medunda show CLI tool to display available variables and providers, supported by provider-level descriptions and a new tabulate dependency to format the output.

Changes:

• Added an abstract Provider.get_description() API and implemented it for all existing providers.
• Introduced medunda show variables|providers subcommands (with optional provider/frequency filtering for variables).
• Added tabulate to project dependencies and updated the lockfile.

Reviewed changes

Copilot reviewed 6 out of 7 changed files in this pull request and generated 8 comments.

Show a summary per file

File	Description
src/medunda/__main__.py	Adds the show CLI command and table rendering via tabulate.
src/medunda/providers/provider.py	Adds new abstract get_description() provider API.
src/medunda/providers/cmems.py	Implements get_description() for CMEMS providers.
src/medunda/providers/local_reanalysis.py	Implements get_description() for LocalReanalysis provider.
src/medunda/providers/tar_archive.py	Implements get_description() for TarArchive provider.
pyproject.toml	Adds tabulate runtime dependency.
poetry.lock	Regenerated lockfile, including tabulate and many other dependency updates.

---

💡 Add Copilot custom instructions for smarter, more guided reviews. Learn how to get started.