Store cask metadata as JSON more often

[MikeMcQuaid]

• Use a minimal post-install snapshot for supported casks.
• Read receipt-owned version and artifacts from INSTALL_RECEIPT.json.
• Leave uninstall flight block caskfiles as Ruby until ported.

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[Copilot]

Pull request overview

This PR shifts Homebrew Cask “installed caskfile” metadata toward a minimal, post-install JSON snapshot for more casks, relying on INSTALL_RECEIPT.json for receipt-owned data (e.g., version and uninstall artifacts) while keeping Ruby metadata for casks that still require uninstall flight blocks.

Changes:

• Write installed cask metadata as <token>.json for most casks, falling back to <token>.rb when uninstall flight blocks are present.
• Load installed casks via load_from_installed_caskfile, and hydrate missing receipt-owned fields when loading from installed JSON.
• Update and add tests to reflect the new installed-metadata behavior and edge cases.

Reviewed changes

Copilot reviewed 11 out of 11 changed files in this pull request and generated 2 comments.

Show a summary per file

File	Description
Library/Homebrew/test/cmd/upgrade_spec.rb	Adjusts expectations and fixtures to reflect installed cask metadata moving to .json.
Library/Homebrew/test/cmd/uninstall_spec.rb	Updates trust/untrusted-tap uninstall coverage for JSON-installed metadata and Ruby fallbacks.
Library/Homebrew/test/cmd/doctor_spec.rb	Mirrors upgrade/doctor expectations for .json installed metadata.
Library/Homebrew/test/cask/upgrade_spec.rb	Switches stubbing to load_from_installed_caskfile for installed-metadata error paths.
Library/Homebrew/test/cask/installer_spec.rb	Adds coverage for JSON-installed metadata shape, only_path preservation, and Ruby fallback for uninstall flight blocks.
Library/Homebrew/json_api_postinstall_preflight_postflight_plan.md	Documents the intended installed metadata format and migration direction.
Library/Homebrew/cask/upgrade.rb	Uses load_from_installed_caskfile and simplifies invalid-installed-metadata handling.
Library/Homebrew/cask/installer.rb	Changes installed-metadata writing logic: Ruby only for uninstall flight blocks, otherwise minimal JSON.
Library/Homebrew/cask/caskroom.rb	Reorders preferred installed caskfile extensions to prefer .json.
Library/Homebrew/cask/cask.rb	Adds to_installed_json_hash to generate the minimal installed JSON snapshot.
Library/Homebrew/cask/cask_loader.rb	Permits empty JSON only for installed caskfiles and hydrates version/artifacts when loading installed JSON.

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[p-linnane]

Love this.