R-488: backup tests read ONE health-wait clock; package 444 s -> ~2 s

waitForHealthy's 3 s settle / 5 s poll / 90 s timeout become package vars (production values
unchanged, pinned by TestR488_HealthWaitDefaultsAreProduction); TestMain shortens them once.
Measured before: 51 of 599 tests held 442 of 444 s, two not-running fixtures 279 s alone.
newOffboxManager now installs a failing SSH fake: TestOffbox_ConfirmedReset was spawning a
real 'ssh felhom@nas.local' and waiting out its 10 s ConnectTimeout.

Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_0159rPz1ZhFKsS53msqPYxtS

controller/internal/backup/restore.go

@@ -87,7 +87,7 @@ func (m *Manager) RestoreApp(stackName, snapshotID string) error {
 	}
 
 	// Verify app started successfully
-	if err := m.waitForHealthy(stackName, 90*time.Second); err != nil {
+	if err := m.waitForHealthy(stackName, healthTimeout); err != nil {
 		m.logger.Printf("[WARN] [backup] Restore completed but app health check failed: %v", err)
 	}
 
@@ -203,13 +203,23 @@ func (m *Manager) restoreDockerVolumesFrom(stackName, dumpDir string) (int, erro
 	return restored, nil
 }
 
+// waitForHealthy's clock (R-488). These are the PRODUCTION values; they are variables only so the
+// package's tests can shorten them in ONE place (main_test.go TestMain) instead of every restore
+// test sleeping 3 s of settle and every not-running fixture waiting out the full 90 s — that was
+// ~280 s of the package's ~440 s. TestR488_HealthWaitDefaultsAreProduction pins the values.
+var (
+	healthSettle   = 3 * time.Second  // initial settling time before the first poll
+	healthInterval = 5 * time.Second  // between polls
+	healthTimeout  = 90 * time.Second // how long a restored stack gets to reach running
+)
+
 // waitForHealthy waits for a stack to reach running state after restore.
 // Forces a docker ps refresh on each poll to avoid stale state.
 func (m *Manager) waitForHealthy(stackName string, timeout time.Duration) error {
 	deadline := time.Now().Add(timeout)
-	interval := 5 * time.Second
+	interval := healthInterval
 
-	time.Sleep(3 * time.Second) // initial settling time
+	time.Sleep(healthSettle) // initial settling time
 
 	for time.Now().Before(deadline) {
 		if m.stackProvider == nil {