Share full-name parsing helpers

[MikeMcQuaid]

• keep full_name parsing consistent across formula and cask code
• reduce repeated split("/") logic so tap and name extraction do not drift in commands, bundle code, and migrations
• cover Utils.name_from_full_name and Utils.tap_from_full_name in test/utils_spec.rb

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[Copilot]

Pull request overview

This PR centralizes parsing of tap-qualified “full names” into Utils helpers to keep formula/cask name and tap extraction consistent across Homebrew commands, Bundle code, and migration/auditing paths.

Changes:

• Add Utils.name_from_full_name and Utils.tap_from_full_name helpers plus unit tests.
• Replace repeated split("/")/rpartition("/") parsing across commands, Bundle, and audit/diagnostic code with the helpers.
• Minor cleanup in an RBI file (remove a stray trailing line).

Reviewed changes

Copilot reviewed 23 out of 24 changed files in this pull request and generated 2 comments.

Show a summary per file

File	Description
Library/Homebrew/utils.rb	Adds shared full-name parsing helpers (name_from_full_name, tap_from_full_name).
Library/Homebrew/test/utils_spec.rb	Adds unit tests for the new parsing helpers.
Library/Homebrew/test/bundle/commands/cleanup_spec.rb	Updates Bundle cleanup specs to use the helpers and requires utils.
Library/Homebrew/tap_auditor.rb	Uses helper for extracting short names from tap-provided token/full-name lists.
Library/Homebrew/missing_formula.rb	Refactors tap migration messaging to use helpers (introduces an uncovered edge-case).
Library/Homebrew/migrator.rb	Uses helper to derive tap names from migration targets.
Library/Homebrew/linkage_checker.rb	Uses helper to extract dependency names from possibly tap-qualified names.
Library/Homebrew/language/python.rb	Uses helper when matching requirements/deps against the chosen Python dependency name.
Library/Homebrew/formulary.rb	Uses helper for alias-table short-name extraction.
Library/Homebrew/formula.rb	Uses helper when deriving aliases and enumerating tap formula/alias names.
Library/Homebrew/formula_auditor.rb	Uses helper to compare dependency oldnames against dep short name.
Library/Homebrew/extend/hash/deep_transform_values.rbi	Removes an extraneous trailing blank line.
Library/Homebrew/diagnostic.rb	Uses helper to extract tap names for shadowed formula/cask reporting.
Library/Homebrew/dev-cmd/bottle.rb	Uses helper to compute short formula name for bottle commit messages.
Library/Homebrew/descriptions.rb	Uses helper to build a map of short names for display.
Library/Homebrew/dependency.rb	Uses helper for option_names derived from dependency name.
Library/Homebrew/cmd/update-report.rb	Uses helpers for rename/migration parsing in update report generation and migration actions.
Library/Homebrew/cmd/untap.rb	Uses helper to match installed formulae/casks against tap entries (missing require "utils").
Library/Homebrew/cmd/leaves.rb	Uses helper instead of local base-name parsing for dependency name extraction.
Library/Homebrew/cli/named_args.rb	Uses helpers when raising tap-qualified unavailable errors.
Library/Homebrew/bundle/dsl.rb	Uses helper in cask-name sanitization.
Library/Homebrew/bundle/cask.rb	Uses helpers when checking installed taps and comparing cask names/oldnames.
Library/Homebrew/bundle/brew.rb	Uses helpers in array checks, oldname/alias handling, and entry initialization.
Library/Homebrew/bundle/brew_services.rb	Uses helper for base-name resolution when matching started services and old names.

Files not reviewed (1)

• Library/Homebrew/extend/hash/deep_transform_values.rbi: Language not supported

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[ZhongRuoyu]

Nice cleanup, thanks!