Align ask dry-run prompts

[MikeMcQuaid]

• Use dry-run-style --ask plans for install and reinstall commands.
• Make single-package operations proceed without a prompt e.g. if you brew install foo and there's no dependencies or dependents to install: just install without the prompt.
• Keep prompting when dependencies or dependents change the plan.

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[Copilot]

Pull request overview

This PR adjusts --ask behavior for install/reinstall/upgrade to use --dry-run-style “Would …” plans, and to only prompt when the plan extends beyond what the user explicitly requested (e.g., dependencies/dependents).

Changes:

• Reworked Install.ask_formulae/ask_casks output to match dry-run-style plans and introduced shared prompt decision logic (ask_prompt_needed?).
• Updated brew install/reinstall to pass explicit flags into ask_formulae (instead of passing args) and updated CLI help text + specs to match new output.
• Updated brew upgrade --ask to decide prompting based on the final dry-run plan vs. requested names, including dependency/dependent-driven plan expansion.

Reviewed changes

Copilot reviewed 7 out of 7 changed files in this pull request and generated 3 comments.

Show a summary per file

File	Description
Library/Homebrew/install.rb	Refactors --ask plan printing and introduces shared prompt gating logic.
Library/Homebrew/cmd/install.rb	Uses new ask_formulae signature; --ask help text now references dry-run plan.
Library/Homebrew/cmd/reinstall.rb	Uses new ask_formulae signature; --ask help text simplified to dry-run-style description.
Library/Homebrew/cmd/upgrade.rb	Adds prompt gating based on planned vs requested upgrades and tracks whether dependencies require prompting.
Library/Homebrew/test/cmd/install_spec.rb	Updates expectations to dry-run-style output and adds prompt-rule coverage.
Library/Homebrew/test/cmd/reinstall_spec.rb	Updates --ask output expectation to new “Would reinstall …” format.
Library/Homebrew/test/cmd/upgrade_spec.rb	Adds coverage that explicitly-named upgrades don’t prompt when nothing else changes the plan.

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[Copilot]

Pull request overview

Copilot reviewed 7 out of 7 changed files in this pull request and generated 1 comment.