upgrade: add final summary

[MikeMcQuaid]

Requested in our user survey.

• Make brew upgrade easier to scan after noisy output.
• Preserve existing progress output while narrowing the final view.
• Reuse selected formula and cask upgrade data instead of re-querying.

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OpenAI Codex xhigh with manual review and testing.

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[Copilot]

Pull request overview

Adds a “Final upgrade summary” to brew upgrade output to make end-of-run results easier to scan, while reusing information already gathered during the upgrade (rather than re-querying).

Changes:

• Track upgrade details (version changes, pinned, deprecated/disabled involvement, and formulae building from source) during formula/cask upgrade execution.
• Print a narrow “Final upgrade summary” at the end of brew upgrade.
• Add/extend unit test coverage for summary recording and output formatting.

Reviewed changes

Copilot reviewed 4 out of 4 changed files in this pull request and generated no comments.

File	Description
Library/Homebrew/cmd/upgrade.rb	Introduces FinalUpgradeSummary, records summary data during upgrades, and prints a final summary at the end of the command.
Library/Homebrew/cask/upgrade.rb	Adds optional “summary” accumulator arrays to collect cask upgrade/deprecation/disabled info during cask selection/upgrade.
Library/Homebrew/test/cmd/upgrade_spec.rb	Adds tests for final summary printing and for recording formula-related summary fields.
Library/Homebrew/test/cask/upgrade_spec.rb	Adds tests for recording cask-related summary fields (upgrades, deprecated, disabled).

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