ProdDash Viewer 1.0.0: a Mac app that only shows ProdDash, with a tab per installation

A new Apple-silicon app in viewer/macos (Swift, no dependencies, ~1 MB): one
window showing a ProdDash dashboard in WebKit, and nothing else. It runs no
server; it points at any ProdDash on the network.

- Connections (name + address) in Settings; the add/edit sheet asks
  /api/modules whether ProdDash answers as you type. No port means 24500.
- Two or more connections bring a slim tab bar of their names. In a window
  it floats over the dashboard and comes out while the pointer is on the
  title bar; it is not part of the title bar, because anything there makes
  WebKit push the page down. In full screen it is a titlebar accessory that
  comes down with the menu bar, and it flashes up after each switch.
  ⌃Tab / ⌃⇧Tab and ⌘1–9 switch from the keyboard.
- Full screen, reopening in full screen if it quit there; window size and
  the selected tab are kept too. The dashboard's own full-screen button
  works as well.
- Menus: View (Back, Forward, Reload Page, Enter Full Screen), Settings,
  Edit (copy/paste in the page's text fields), Window, Help (a guide that
  ships in the app).
- Every installation keeps its own live web view. One that can't be
  reached says why and retries at 2, 4, 8, then every 15 s; a redirect off
  the installation is reported, not handed to the browser. JS alert,
  confirm and prompt show as sheets; links to other sites open in the
  browser.
- General settings: open at login (SMAppService), keep the display awake
  while a dashboard is on screen (default on).

build.sh signs with the Developer ID when one is installed and makes a
notarised DMG with --notarize, as the launcher's does. It needs Xcode: with
only the command line tools the macOS 27 SDK can't expand SwiftUI's @State.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

README.md

@@ -618,6 +618,19 @@ sheet's notes, as ProPresenter does for Vista — point Vista Cues' first
 sender at `127.0.0.1:5104` and paste the sheet it prints). See the testing section of
 the [module guide](docs/MODULE-GUIDE.md).
 
+## ProdDash Viewer — a Mac that only shows the dashboard
+
+For a Mac that should show ProdDash and nothing else — a booth display, a
+second screen watching the other campus — there is **ProdDash Viewer**
+([viewer/macos](viewer/macos)): one window, the dashboard, and a slim
+auto-hiding tab bar when it is set up with more than one installation. It
+runs no server of its own; point it at any ProdDash on the network. Full
+screen, reopening as it was left, and keeping the display awake are built in.
+
+```bash
+cd viewer/macos && ./build.sh --dmg
+```
+
 ## Install as a desktop web app
 
 Open the page in a browser first, then:
@@ -648,6 +661,9 @@ ProdDash/
 ├── package.json               name + version (what the update check compares)
 ├── config/                    proddash.json defaults (runtime state lives in the
 │                              per-machine data directory — see "Configure")
+├── launcher/macos/            the macOS app: menu-bar launcher carrying the server
+│                              and its own Node (launcher/windows: the Windows bundle)
+├── viewer/macos/              ProdDash Viewer: a Mac app that only shows dashboards
 ├── docs/MODULE-GUIDE.md       how to build and install a module
 ├── docs/ALERTS.md             the alerts feature: levels, channels, admin, API
 ├── tools/prodcom-mock.js      mock ProdCom API for development