Ship ProdDash as one app: its own Node, its own copy, a .dmg

Installing is dragging ProdDash to Applications. The app carries the
dashboard and the Node that runs it, so nothing has to be installed first and
nothing can go missing underneath it.

  ProdDash.app/Contents/
    MacOS/ProdDash            the launcher
    Resources/node/bin/node   Node 24.21.0 LTS, fetched and checksum-verified
    Resources/app/            server.js, public/, modules/

Everything mutable stays where it already was, in ~/Library/Application
Support/ProdDash — and that now includes app/, the copy of ProdDash that
actually runs. The copy is not ceremony: ProdDash updates itself in place,
and nothing may write inside a signed .app. So the bundle holds a read-only
baseline and the data directory holds the running copy, which means both
routes to a new version keep working and don't fight — installing a newer
.app replaces the copy, while a copy that has already updated itself past the
bundle is left alone.

build.sh now assembles all of it: fetches Node against nodejs.org's published
checksums (cached in .cache/), embeds the server, compiles each module's
native helper so the Mac running ProdDash needs no compiler, signs nested
code before the bundle, and builds the disk image. --dev skips the payload
for launcher work, which still runs against a checkout.

Signing is set up for a Developer ID with the hardened runtime and
notarisation (--notarize), and falls back to ad-hoc when no such certificate
is installed. Entitlements are split by what each binary actually does: JIT
for node, audio input for the launcher and for module helpers that read one.

Built and run end to end: first-run install, bundled node, dashboard and
admin serving, re-seed in both directions (newer app replaces an older copy;
an updated copy survives), disk image mounts and its app verifies.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

launcher/macos/Sources/LauncherConfig.swift

@@ -32,6 +32,95 @@ enum ProdDash {
             .appendingPathComponent("Library/Application Support/ProdDash")
     }
 
+    // MARK: - What the app carries
+
+    /**
+     A shipped ProdDash lives read-only inside the app bundle and runs from a
+     copy in the data directory.
+
+     The copy isn't ceremony: ProdDash updates itself in place — the admin
+     page's "Update now" writes a fresh download over the app folder — and
+     nothing may write inside a signed .app without breaking its signature.
+     So the bundle carries the baseline, the data directory carries the copy
+     that actually runs, and both routes to a new version keep working: drop
+     in a newer .app, or press Update now.
+
+     A development build ships no payload and falls through to the checkout it
+     was built in.
+     */
+    static func bundledPayload() -> URL? {
+        guard let resources = Bundle.main.resourceURL else { return nil }
+        let payload = resources.appendingPathComponent("app")
+        return isRoot(payload) ? payload : nil
+    }
+
+    /// The Node the app carries, so nothing depends on what this Mac happens
+    /// to have installed — or on it staying installed.
+    static func bundledNode() -> URL? {
+        guard let resources = Bundle.main.resourceURL else { return nil }
+        let node = resources.appendingPathComponent("node/bin/node")
+        return FileManager.default.isExecutableFile(atPath: node.path) ? node : nil
+    }
+
+    static func workingCopy(dataDir: URL) -> URL { dataDir.appendingPathComponent("app") }
+
+    /**
+     Put the bundled ProdDash in place: when there is no copy yet, or when the
+     app carries a newer one than the copy — someone installed a new .app. A
+     copy that has updated itself *past* the bundle is left alone, so a new
+     install never drags a running system backwards.
+     */
+    @discardableResult
+    static func seedWorkingCopy(dataDir: URL, log: (String) -> Void) -> URL? {
+        guard let payload = bundledPayload() else { return nil }
+        let working = workingCopy(dataDir: dataDir)
+        let shipped = shellVersion(root: payload)
+        if isRoot(working) {
+            let installed = shellVersion(root: working)
+            guard compareVersions(shipped, installed) > 0 else { return working }
+            log("this app carries ProdDash \(shipped) — replacing the \(installed) copy it runs")
+        } else {
+            log("first run — installing ProdDash \(shipped)")
+        }
+
+        let fm = FileManager.default
+        let previous = working.appendingPathExtension("previous")
+        do {
+            try fm.createDirectory(at: dataDir, withIntermediateDirectories: true)
+            try? fm.removeItem(at: previous)
+            if fm.fileExists(atPath: working.path) { try fm.moveItem(at: working, to: previous) }
+            try fm.copyItem(at: payload, to: working)
+            makeWritable(working)
+            try? fm.removeItem(at: previous)
+            return working
+        } catch {
+            log("could not install the bundled ProdDash: \(error.localizedDescription)")
+            // Put back whatever was working before rather than leaving nothing.
+            if !fm.fileExists(atPath: working.path), fm.fileExists(atPath: previous.path) {
+                try? fm.moveItem(at: previous, to: working)
+            }
+            return isRoot(working) ? working : nil
+        }
+    }
+
+    /// Files copied out of a bundle can arrive read-only, and this copy is
+    /// exactly where ProdDash writes its own updates.
+    private static func makeWritable(_ root: URL) {
+        let fm = FileManager.default
+        var targets = [root]
+        if let walker = fm.enumerator(at: root, includingPropertiesForKeys: nil) {
+            for case let url as URL in walker { targets.append(url) }
+        }
+        for url in targets {
+            guard let mode = (try? fm.attributesOfItem(atPath: url.path))?[.posixPermissions] as? NSNumber
+            else { continue }
+            let writable = mode.uint16Value | 0o200
+            if writable != mode.uint16Value {
+                try? fm.setAttributes([.posixPermissions: NSNumber(value: writable)], ofItemAtPath: url.path)
+            }
+        }
+    }
+
     // MARK: - Finding the checkout
 
     /// A folder is ProdDash if it has the two files the server cannot run without.
@@ -46,7 +135,7 @@ enum ProdDash {
      this .app was built inside (the app usually sits in `launcher/macos/build`),
      else the handful of places people actually keep it.
      */
-    static func findRoot(preferred: String?) -> URL? {
+    static func findRoot(preferred: String?, dataDir: URL) -> URL? {
         if let preferred, !preferred.isEmpty {
             let url = URL(fileURLWithPath: preferred).standardizedFileURL
             if isRoot(url) { return url }
@@ -55,6 +144,12 @@ enum ProdDash {
             let url = URL(fileURLWithPath: env).standardizedFileURL
             if isRoot(url) { return url }
         }
+        // A shipped app runs the copy it installed; only a development build
+        // (no payload) goes looking for a checkout.
+        if bundledPayload() != nil {
+            let working = workingCopy(dataDir: dataDir)
+            if isRoot(working) { return working }
+        }
         var up = Bundle.main.bundleURL.standardizedFileURL
         for _ in 0..<6 {
             up.deleteLastPathComponent()
@@ -89,6 +184,8 @@ enum ProdDash {
     static func findNode(root: URL?, preferred: String?) -> URL? {
         var tries: [URL] = []
         if let preferred, !preferred.isEmpty { tries.append(URL(fileURLWithPath: preferred)) }
+        // What the app carries, so a shipped ProdDash needs nothing installed.
+        if let bundled = bundledNode() { tries.append(bundled) }
         // The runtime a production machine ships with — same preference as Start ProdDash.command.
         if let root { tries.append(root.appendingPathComponent("runtime/bin/node")) }
         tries += ["/opt/homebrew/bin/node", "/usr/local/bin/node", "/opt/local/bin/node", "/usr/bin/node"]