feat: allow index names without Collections suffix

[pvl]

Description

Currently, all indexes created in the application automatically receive a "Collections" suffix, which can result in index names that are too long, especially when the index name already has multiple words. This can cause issues when there are many collections (e.g. 15 or more), as the longer names may not fit in the space for the tabs in the Files section.

To address this, it would be good to allow users to choose the full name for each index, rather than automatically appending the "Collections" suffix.

Notice this change has an impact on previously created collections (the suffix Collections is removed, the suffix would need to be manually added back if wanted).

Type of change

• New features (non-breaking change).
• Bug fix (non-breaking change).
• Breaking change (fix or feature that would cause existing functionality not to work as expected).

Checklist

• I have performed a self-review of my code.
• I have added thorough tests if it is a core feature.
• There is a reference to the original bug report and related work.
• I have commented on my code, particularly in hard-to-understand areas.
• The feature is well documented.