Use rule display name as profile rule name default

[eleftherias]

If a profile does not have a custom name set for the rule, then the rule display name should be used as a default.

Summary

If a profile does not have a custom name set for the rule, then the rule type display name should be used as a default.
If neither of the above exist, then the rule type name should be used.

Fixes #4251

Examples

Profile doesn't have custom rule name overrides. Rule types all have display names.

Profile has some custom rule name overrides. Rule types all have display names.

Profile has some custom rule name overrides. Rule types don't have display names.

Profile doesn't have custom rule name overrides. Rule types don't have display names.

Change Type

Mark the type of change your PR introduces:

• Bug fix (resolves an issue without affecting existing features)
• Feature (adds new functionality without breaking changes)
• Breaking change (may impact existing functionalities or require documentation updates)
• Documentation (updates or additions to documentation)
• Refactoring or test improvements (no bug fixes or new functionality)

Testing

Outline how the changes were tested, including steps to reproduce and any relevant configurations.
Attach screenshots if helpful.

Review Checklist:

• Reviewed my own code for quality and clarity.
• Added comments to complex or tricky code sections.
• Updated any affected documentation.
• Included tests that validate the fix or feature.
• Checked that related changes are merged.

[coveralls]

coverage: 53.312% (+0.03%) from 53.28%
when pulling 1201dc9 on eleftherias:4251-profile-rule-display-name
into 9a554ef on stacklok:main.

[evankanderson]

Can you check that this produces expected results when you go a get of the profile after creating it?