fix: preserve dotted catalog names in validate -a

[MatteoFari]

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Documentation (change which affects the documentation site)
• Breaking change (fix or feature that would cause existing functionality to change)

Quality assurance (all should be covered).

• My code follows the code style of this project.
• Documentation for my change is up to date?
• My PR meets testing requirements.
• All new and existing tests passed.
• All commits are signed-off.

Summary

Fixes trestle validate -a when a top-level catalog directory contains a . in its name, for example catalogs/foo.bar.

This change preserves the full directory name by using Path.name for top-level model discovery.

Key links:

• Closes trestle validate -a fails if there is a catalog colder with "." in its name #2145
• Sonar coverage