feat: release 1.4.0 with isolated upgrades and device discovery

scripts/installation_lock.ps1

@@ -0,0 +1,20 @@
+# Shared preparation/upgrade mutex. ASCII for Windows PowerShell 5.1.
+function Enter-ArtemisInstallationLock {
+    param([string]$ProjectRoot)
+    $normalized = [IO.Path]::GetFullPath($ProjectRoot).TrimEnd('\').ToLowerInvariant()
+    $hash = [Security.Cryptography.SHA256]::Create()
+    try { $digest = [BitConverter]::ToString($hash.ComputeHash([Text.Encoding]::UTF8.GetBytes($normalized))).Replace('-', '') }
+    finally { $hash.Dispose() }
+    $mutex = New-Object Threading.Mutex($false, "Local\ArtemisInstallation-$digest")
+    try {
+        try { $entered = $mutex.WaitOne(0) }
+        catch [Threading.AbandonedMutexException] { $entered = $true }
+        if (-not $entered) { throw 'Another startup preparation or upgrade is running. Please wait and retry.' }
+        return $mutex
+    } catch { $mutex.Dispose(); throw }
+}
+
+function Exit-ArtemisInstallationLock {
+    param($Mutex)
+    if ($null -ne $Mutex) { $Mutex.ReleaseMutex(); $Mutex.Dispose() }
+}