ci: run rubocop

[jkowalleck]

Description

run RuboCop in CI -- fixing things is out of scope

Resolves or fixes issue: #68

AI Tool Disclosure

• My contribution does not include any AI-generated content
• My contribution includes AI-generated content, as disclosed below:
  • AI Tools: [e.g. GitHub CoPilot, ChatGPT, JetBrains Junie etc.]
  • LLMs and versions: [e.g. GPT-4.1, Claude Haiku 4.5, Gemini 2.5 Pro etc.]
  • Prompts: [Summarize the key prompts or instructions given to the AI tools]

Affirmation

• My code follows the CONTRIBUTING.md guidelines

[codacy-production]

Up to standards ✅

🟢 Issues 0 issues

Results:
0 new issues

View in Codacy

🟢 Coverage ∅ diff coverage · +0.00% coverage variation

Metric	Results
Coverage variation	✅ +0.00% coverage variation (-1.00%)
Diff coverage	✅ ∅ diff coverage

View coverage diff in Codacy

Coverage variation details

	Coverable lines	Covered lines	Coverage
Common ancestor commit (b3a472f)	274	240	87.59%
Head commit (34132d7)	274 (+0)	240 (+0)	87.59% (+0.00%)

Coverage variation is the difference between the coverage for the head and common ancestor commits of the pull request branch: <coverage of head commit> - <coverage of common ancestor commit>

Diff coverage details

	Coverable lines	Covered lines	Diff coverage
Pull request (#69)	0	0	∅ (not applicable)

Diff coverage is the percentage of lines that are covered by tests out of the coverable lines that the pull request added or modified: <covered lines added or modified>/<coverable lines added or modified> * 100%

_{NEW Get contextual insights on your PRs based on Codacy's metrics, along with PR and Jira context, without leaving GitHub. Enable AI reviewer
TIP This summary will be updated as you push new changes.}