feat(cli): support multiple output formats via --formats flag

[JuanVqz]

Context

We added support to JSON, and HTML reports.

Done When

We can generate those reports with the --formats flag

skunk . --formats console,json,html # if you need the 3 format reports
skunk app lib --formats json # will only save the json result at `tmp/rubycritic/skunk_report.json`
skunk app # will use console format by default

[Copilot]

Pull Request Overview

This PR adds support for multiple output formats (JSON, HTML, console) through a new --formats CLI flag, allowing users to generate one or more report types in a single run.

Key Changes:

• Introduced --formats flag to CLI with support for comma-separated format values (json, html, console)
• Added parsing logic to convert format strings to symbols and store in Skunk::Config
• Updated documentation to explain CLI and programmatic format configuration

Reviewed Changes

Copilot reviewed 6 out of 6 changed files in this pull request and generated no comments.

Show a summary per file

File	Description
lib/skunk/cli/options/argv.rb	Adds --formats flag parser that accepts comma-separated formats and stores them in Config
test/lib/skunk/cli/options/argv_test.rb	Adds test coverage for the new --formats option parsing
test/lib/skunk/commands/help_test.rb	Updates help text to include the new --formats flag
README.md	Documents CLI flag usage and programmatic configuration for output formats
CHANGELOG.md	Records the new feature addition
.rubocop_todo.yml	Updates RuboCop offense counts and removes resolved line length violations

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[etagwerker]

@JuanVqz Changes look good, I just added one comment related to default

[etagwerker]

@JuanVqz Unfortunately now I'm getting non-deterministic failures from the test suite and it seems to be related to these changes.

https://gist.github.com/etagwerker/9ac9d8e20b5f5a4789b5fe263946c211

1 or 2 out of 10 test executions will fail with something like that.

Could you please take a look?