chore: upgrade RuboCop to 1.88.2

[coderabbitai]

Summary

Upgrade the repository's RuboCop dependency from the currently pinned legacy version to RuboCop 1.88.2.

Rationale

The current RuboCop version is substantially behind the requested target and lacks newer cop names and behavior, such as Naming/PredicatePrefix. Updating keeps linting rules and inline directives aligned with supported RuboCop behavior.

Affected areas

• Root and package Gemfile / lockfile dependency declarations that pin or resolve RuboCop
• RuboCop configuration files
• Existing inline rubocop:disable / rubocop:enable directives and any rules renamed or changed by the upgrade
• CI or local linting documentation/scripts, if they reference the current version

Acceptance criteria

• RuboCop is upgraded to version 1.88.2.
• Related RuboCop plugins and configuration remain compatible.
• Existing configuration and inline directives are updated for renamed, removed, or changed cops as necessary.
• The repository's documented linting workflow completes successfully with the upgraded dependency.

Requested by: @juliolmuller

Related PR: #27
Related review comment: #27 (comment)