Read only config

[graeme]

PR: Make Config feature read-only; remove env file editing

Summary

Removes all brew.env read/write infrastructure from the Config feature, making the Configuration page a read-only view of brew config output. The env-file editor added complexity and surface area that wasn't justified by the current UX; stripping it out brings the feature back to a simple, correct display of the config snapshot.

Changes

• Deleted BrewEnvFile model and all CLI-layer env file code — BrewEnvFileLocator, BrewEnvFileParser, BrewEnvFileWriter and the BrewEnvFile domain model are gone.
• Removed EnvFileRepository protocol and implementation — BrewEnvFileRepository and the EnvFileRepository protocol are deleted, along with their registration in RepositoryEnvironment and the unimplemented stub.
• Slimmed ConfigViewModel from ~400 lines to ~50 — draft state, dirty tracking, save/revert logic, dangerous-key confirmation flow, and pageState combining both repositories are all removed. The VM now exposes a single pageState: LoadState<BrewConfigSnapshot, String> backed only by ConfigRepository.
• Deleted editor-only ViewModels — CaskOpts, ConfigPagePayload, EnvKeyDescriptor, EnvRowItem are removed entirely.
• Removed ConfigEnvironmentEditorCard — the 365-line editor view is gone; ConfigView and ConfigColumnsRoot updated accordingly.
• Added BrewConfigSnapshot+Placeholdable — small extension to support redacted placeholder rendering on the now-simplified config view.
• Deleted all associated tests — BrewEnvFileBrewSemanticsTests, BrewEnvFileLocatorTests, BrewEnvFileParserTests, BrewEnvFileWriterTests, BrewEnvFileRepositoryTests, CaskOptsTests, ConfigViewModelAdvancedTests, and ConfigViewModelEditingTests are removed. ConfigViewModelTests is trimmed to match the reduced VM surface.

Net: −3,333 lines, +49.

Why this split

The env-file writer was built speculatively. Keeping it required maintaining a parallel load/sync path alongside the config snapshot, handling merge conflicts between external file changes and in-progress edits, and classifying keys as dangerous or read-only — all for a feature that doesn't ship yet. Removing it now leaves a clean foundation; editing can be re-introduced as a deliberate, scoped piece of work if needed.

Testing

• swift test --filter ConfigViewModelTests — all remaining config VM tests pass.
• App builds and the Configuration tab loads and displays the brew config snapshot correctly.
• No references to deleted types remain in the compiled target.

PR checklist

• Have you followed this repository's contribution and workflow guidance?
• Have you explained what changed and why this should land now?
• Have you run relevant local checks for the changed scope?
• Are changes scoped and free of unrelated modifications?

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• AI was used to generate or assist with generating this PR.
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  Claude Code removed most of the code and drafted this description from git diff main...HEAD. The diff, commit messages, and deleted files were reviewed manually to confirm accuracy before filing.

[Copilot]

Pull request overview

This PR simplifies the Config feature by removing all brew.env read/write/editing infrastructure, leaving the Configuration page as a read-only view backed solely by the brew config snapshot.

Changes:

• Removed the brew.env domain model, parser/writer/locator, repository interface + implementation, and all related tests.
• Simplified ConfigViewModel and views to load/render only ConfigRepository state (read-only; copy/refresh only).
• Added BrewConfigSnapshot: Placeholdable to support AsyncContentView’s redacted placeholder rendering after the VM simplification.

Reviewed changes

Copilot reviewed 30 out of 30 changed files in this pull request and generated no comments.

Show a summary per file

File	Description
Tests/BrewRepositoriesTests/BrewEnvFileRepositoryTests.swift	Deleted env-file repository tests (env editing removed).
Tests/BrewFeatureConfigTests/ConfigViewModelTests.swift	Updated tests for the simplified ConfigViewModel init and behavior.
Tests/BrewFeatureConfigTests/ConfigViewModelEditingTests.swift	Deleted editor-flow tests (editing removed).
Tests/BrewFeatureConfigTests/ConfigViewModelAdvancedTests.swift	Deleted advanced editor behavior tests (editing removed).
Tests/BrewFeatureConfigTests/CaskOptsTests.swift	Deleted HOMEBREW_CASK_OPTS advisory tests (editor removed).
Tests/BrewCLITests/BrewEnvFileWriterTests.swift	Deleted env-file writer tests (writer removed).
Tests/BrewCLITests/BrewEnvFileParserTests.swift	Deleted env-file parser tests (parser removed).
Tests/BrewCLITests/BrewEnvFileLocatorTests.swift	Deleted env-file locator tests (locator removed).
Tests/BrewCLITests/BrewEnvFileBrewSemanticsTests.swift	Deleted brew.env semantics tests (feature removed).
Sources/BrewRepositoryInterfaces/Protocols/EnvFileRepository.swift	Deleted EnvFileRepository protocol.
Sources/BrewRepositoryInterfaces/PreviewSupport/PreviewSupport.swift	Removed env-file preview repository wiring.
Sources/BrewRepositoryInterfaces/Fakes/Stubs.swift	Removed StubEnvFileRepository fake.
Sources/BrewRepositories/BrewEnvFileRepository.swift	Deleted live brew.env repository implementation.
Sources/BrewFeatureConfig/Views/ConfigView.swift	Removed save/discard/editor UI; now copy/refresh + read-only cards.
Sources/BrewFeatureConfig/Views/ConfigEnvironmentEditorCard.swift	Deleted the environment editor card UI.
Sources/BrewFeatureConfig/Views/ConfigColumnsRoot.swift	Removed env-file repository dependency injection into ConfigView.
Sources/BrewFeatureConfig/ViewModels/EnvRowItem.swift	Deleted editor row model types.
Sources/BrewFeatureConfig/ViewModels/EnvKeyDescriptor.swift	Deleted env key catalogue/descriptor/editor-only types.
Sources/BrewFeatureConfig/ViewModels/ConfigViewModel.swift	Reduced VM to config snapshot load/refresh + error mapping only.
Sources/BrewFeatureConfig/ViewModels/ConfigPagePayload.swift	Deleted combined snapshot+env payload model.
Sources/BrewFeatureConfig/ViewModels/CaskOpts.swift	Deleted cask opts advisory logic (editor removed).
Sources/BrewCore/Models/BrewEnvFile.swift	Deleted BrewEnvFile domain model.
Sources/BrewCore/Models/BrewConfigSnapshot+Placeholdable.swift	Added placeholder snapshot for AsyncContentView loading skeletons.
Sources/BrewCLI/Config/BrewEnvFileWriter.swift	Deleted brew.env writer.
Sources/BrewCLI/Config/BrewEnvFileParser.swift	Deleted brew.env parser.
Sources/BrewCLI/Config/BrewEnvFileLocator.swift	Deleted brew.env locator.
Sources/BrewAppEnvironment/UnimplementedRepositories.swift	Removed unimplemented env-file repository stub.
Sources/BrewAppEnvironment/RepositoryEnvironment.swift	Removed EnvironmentValues.envFileRepository entry.
Homebrew/Features/MainWindow/Views/MainWindowView.swift	Removed env-file repository preview injection.
Homebrew/BrewApp.swift	Removed env-file repository from app composition + scene-phase invalidation.

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