refactor: update type signatures to always return boolean for install…

[hyuraku]

…ed_as_dependency and installed_on_request

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solve the comment # TODO: change this to always return a boolean

[MikeMcQuaid]

Thanks! A few tweaks.

[Copilot]

Pull Request Overview

This PR refactors the installed_as_dependency and installed_on_request attributes in the Tab class to always return boolean values instead of nullable booleans. The change introduces new tracking methods to distinguish between explicitly set false values and unset/missing values.

• Added installed_on_request_present? and installed_as_dependency_present? methods to track whether these attributes were explicitly set
• Updated type signatures from T.nilable(T::Boolean) to T::Boolean with default values of false
• Modified the autoremove logic to check for presence before evaluating the boolean value

Reviewed Changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated 2 comments.

File	Description
Library/Homebrew/tab.rb	Added presence tracking for dependency/request attributes, updated type signatures to non-nullable booleans, and added new predicate methods
Library/Homebrew/utils/autoremove.rb	Updated unused formula detection to check for attribute presence before evaluating boolean values
Library/Homebrew/test/utils/autoremove_spec.rb	Updated test mocks to include the new installed_on_request_present? method

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[MikeMcQuaid]

Thanks @hyuraku!