Harden workspace sync quarantine and updater recovery (#6)

scripts/apply-binary-update.ps1

@@ -63,16 +63,24 @@ function Get-Sha256([string]$Path) {
   }
 }
 
+function Start-ForgeFlowAndVerify([string]$Executable) {
+  $process = Start-Process -FilePath $Executable -WorkingDirectory (Split-Path -Parent $Executable) -PassThru
+  Start-Sleep -Milliseconds 1500
+  if (-not $process -or $process.HasExited) { throw "ForgeFlow restart process exited before the application could stay running." }
+  return $process
+}
+
 try {
-  Write-UpdateState -State "started" -Message "Binary updater owns the update request."
   Write-Log "Validating ForgeFlow $ExpectedVersion binary update."
   if ($HandshakeOnly) {
+    Write-UpdateState -State "started" -Message "Binary updater owns the update request."
     Write-Log "Handshake-only verification completed successfully."
     exit 0
   }
   $actualSha256 = Get-Sha256 -Path $BinaryPath
   if ($actualSha256 -ne $ExpectedSha256.ToLowerInvariant()) { throw "Binary update SHA-256 verification failed." }
   if (-not (Test-Path -LiteralPath $CurrentExecutable -PathType Leaf)) { throw "Current ForgeFlow executable was not found." }
+  Write-UpdateState -State "started" -Message "Binary preflight passed; updater owns the update request."
   if ($VerifyOnly) {
     Write-Log "Verification-only SHA-256 check completed successfully."
     exit 0
@@ -90,9 +98,16 @@ try {
     try {
       Copy-Item -LiteralPath $BinaryPath -Destination $CurrentExecutable -Force
     } catch {
-      Copy-Item -LiteralPath $backupPath -Destination $CurrentExecutable -Force
-      Write-UpdateState -State "rolled-back" -Message $_.Exception.Message
-      throw
+      $copyFailure = $_.Exception.Message
+      try {
+        Copy-Item -LiteralPath $backupPath -Destination $CurrentExecutable -Force
+        $rollbackRestart = Start-ForgeFlowAndVerify -Executable $CurrentExecutable
+        Write-Log "Portable replacement failed; previous ForgeFlow restored and restarted as PID $($rollbackRestart.Id)."
+        Write-UpdateState -State "rolled-back" -Message $copyFailure -RestartLaunched $true
+      } catch {
+        Write-UpdateState -State "failed" -Message "$copyFailure Rollback also failed: $($_.Exception.Message)" -RestartLaunched $false
+      }
+      throw $copyFailure
     }
   } else {
     Write-UpdateState -State "applying" -Message "Running the verified ForgeFlow installer."
@@ -100,13 +115,31 @@ try {
     if ($installer.ExitCode -ne 0) { throw "ForgeFlow installer exited with code $($installer.ExitCode)." }
   }
 
-  $restart = Start-Process -FilePath $CurrentExecutable -WorkingDirectory (Split-Path -Parent $CurrentExecutable) -PassThru
-  Write-Log "ForgeFlow $ExpectedVersion installed; restart PID $($restart.Id)."
-  Write-UpdateState -State "success" -Message "ForgeFlow $ExpectedVersion installed successfully." -RestartLaunched $true
+  try {
+    $restart = Start-ForgeFlowAndVerify -Executable $CurrentExecutable
+    Write-Log "ForgeFlow $ExpectedVersion installed; verified restart PID $($restart.Id)."
+    Write-UpdateState -State "success" -Message "ForgeFlow $ExpectedVersion installed successfully." -RestartLaunched $true
+  } catch {
+    $restartFailure = $_.Exception.Message
+    if ($isPortable -and $backupPath -and (Test-Path -LiteralPath $backupPath -PathType Leaf)) {
+      Write-Log "Updated portable executable failed its restart probe; restoring the previous executable."
+      try {
+        Copy-Item -LiteralPath $backupPath -Destination $CurrentExecutable -Force
+        $rollbackRestart = Start-ForgeFlowAndVerify -Executable $CurrentExecutable
+        Write-Log "Previous ForgeFlow restored and restarted as PID $($rollbackRestart.Id)."
+        Write-UpdateState -State "rolled-back" -Message $restartFailure -RestartLaunched $true
+      } catch {
+        Write-UpdateState -State "failed" -Message "$restartFailure Rollback also failed: $($_.Exception.Message)" -RestartLaunched $false
+      }
+      exit 1
+    }
+    Write-Log "ForgeFlow $ExpectedVersion installed, but automatic restart failed: $restartFailure"
+    Write-UpdateState -State "success" -Message "ForgeFlow $ExpectedVersion installed successfully, but must be started manually." -RestartLaunched $false
+  }
 } catch {
   Write-Log $_.Exception.Message
   $current = $null
   try { $current = Get-Content -LiteralPath $StatusPath -Raw | ConvertFrom-Json } catch {}
-  if ($current.state -ne "rolled-back") { Write-UpdateState -State "failed" -Message $_.Exception.Message }
+  if ($current.state -notin @("rolled-back", "failed")) { Write-UpdateState -State "failed" -Message $_.Exception.Message }
   exit 1
 }