fix: keep window open when pinned

[Gabko14]

Summary

Fixes Ghostly-9k3 — the window was dismissing when switching to a clipboard manager (or any other app) because MenuBarExtraAccess closes the window whenever it loses key status.

• Forked MenuBarExtraAccess locally (LocalPackages/MenuBarExtraAccess) and added a staysOpen: Binding<Bool> parameter to menuBarExtraAccess(). When staysOpen is true, the didResignKey handler skips window.close() so the window stays visible. Explicit dismissal (clicking the status item icon, Escape key) still works correctly.
• Added isPinned: Bool to AppState (stored property, persisted to UserDefaults).
• Wired staysOpen: $appState.isPinned in GhostlyApp.
• Added a pin button (pin icon) to the header, to the left of the menu button. Toggling it pins/unpins the window. State is remembered across launches.

Test plan

• Open Ghostly, click pin icon — it turns lavender/filled
• While pinned, switch to another app (e.g. Finder, clipboard manager) — Ghostly window stays open
• Click pin icon again to unpin — switching apps now closes the window as before
• Escape key and clicking the menu bar icon still close the window even when pinned
• Pin state persists after quitting and relaunching
• All unit tests pass

[claude]

PR Review: fix: keep window open when pinned

Overview

This PR solves a usability problem where the Ghostly window dismisses when switching to another app (e.g., clipboard manager). The approach of forking MenuBarExtraAccess and adding a staysOpen binding is reasonable since the upstream library doesn't support this behavior.

Issues to Address

1. Missing Unit Tests

Per CLAUDE.md: "Nothing ships without automated tests. Write unit tests for all logic/model changes."

The isPinned property in AppState needs tests similar to the existing isMenuPresented tests. At minimum:

• Initial state test (reads from UserDefaults)
• Toggle test
• UserDefaults persistence test (verify didSet writes to UserDefaults)

2. Remove Unused Code File

LocalPackages/MenuBarExtraAccess/Sources/MenuBarExtraAccess/Unused/Unused Code.swift contains 54 lines of entirely commented-out code. This should be deleted — per CLAUDE.md, avoid backwards-compatibility hacks like keeping removed code as comments.

Looks Good

• The staysOpen logic in didResignKey is well-implemented — correctly checks window.isVisible to distinguish between "lost focus" vs "explicitly closed"
• Pin button UI uses Catppuccin tokens (Color.catLavender, Color.catOverlay) consistently
• HeaderView signature change is backwards-compatible via the computed settingsManager property
• License attribution to original author (Steffan Andrews, MIT) is preserved

Minor Note

Consider documenting in the PR body (or a code comment) that this is a fork of orchetect/MenuBarExtraAccess v1.2.2 for future maintainability context.