v0.12.4 — 15 bug fixes (CRITICAL/HIGH/MEDIUM)

CRITICAL:
- C1: SetAppBackupBulk data loss + nil map panic (settings.go)
- C2: UpdateStackConfig nil Env map panic (deploy.go)
- C3: ValidateDump missing scanner.Err() check (dbdump.go)

HIGH:
- H1: nextDailyRun DST bug — use time.Date(day+1) not Add(24h)
- H2: Cache Europe/Budapest timezone with sync.Once in scheduler
- H3: settings.save() leaks .tmp file on WriteFile failure
- H4: SetNotificationPrefs nil pointer panic
- H5: appDirSize + getDirSizeBytes ignore Sscanf return value
- H6: getDirSizeBytes has no timeout — add 30s context
- H7: dbdump.go tmpFile not using defer Close
- H8: UpdateCrossDriveStatus misleading comment

MEDIUM:
- M1: Replace custom containsBytes with strings.Contains
- M2: scheduler.Every() validates interval > 0
- M3: executeJob panic recovery now sets LastRun
- M4: logPostStartStatus copies env slice before goroutine
- M5: Cache timezone in web package via getTimezone() sync.Once

Co-Authored-By: Claude Sonnet 4.5 <noreply@anthropic.com>

controller/internal/stacks/delete.go

@@ -2,6 +2,7 @@ package stacks
 
 import (
 	"bufio"
+	"context"
 	"fmt"
 	"os"
 	"os/exec"
@@ -278,7 +279,9 @@ func getDirSizeHuman(path string) string {
 
 // getDirSizeBytes returns the total size in bytes for a directory.
 func getDirSizeBytes(path string) int64 {
-	cmd := exec.Command("du", "-sb", path)
+	ctx, cancel := context.WithTimeout(context.Background(), 30*time.Second)
+	defer cancel()
+	cmd := exec.CommandContext(ctx, "du", "-sb", path)
 	output, err := cmd.Output()
 	if err != nil {
 		return 0
@@ -286,7 +289,9 @@ func getDirSizeBytes(path string) int64 {
 	fields := strings.Fields(string(output))
 	if len(fields) > 0 {
 		var size int64
-		fmt.Sscanf(fields[0], "%d", &size)
+		if n, _ := fmt.Sscanf(fields[0], "%d", &size); n != 1 {
+			return 0
+		}
 		return size
 	}
 	return 0

controller/internal/stacks/deploy.go

@@ -233,6 +233,10 @@ func (m *Manager) UpdateStackConfig(name string, values map[string]string) error
 		return fmt.Errorf("stack %q is not deployed yet", name)
 	}
 
+	if appCfg.Env == nil {
+		appCfg.Env = make(map[string]string)
+	}
+
 	lockedSet := make(map[string]bool)
 	for _, f := range appCfg.LockedFields {
 		lockedSet[f] = true

controller/internal/stacks/manager.go

@@ -628,10 +628,12 @@ func truncateStr(s string, maxLen int) string {
 // logPostStartStatus queries container states after a start/deploy operation
 // and logs them. This runs asynchronously to avoid blocking the HTTP response.
 func (m *Manager) logPostStartStatus(name, stackDir string, env []string) {
+	envCopy := make([]string, len(env))
+	copy(envCopy, env)
 	go func() {
 		time.Sleep(3 * time.Second)
 
-		output, err := m.composeExecCustomEnv(stackDir, env, "ps", "-a", "--format", "table {{.Name}}\t{{.Image}}\t{{.State}}\t{{.Status}}")
+		output, err := m.composeExecCustomEnv(stackDir, envCopy, "ps", "-a", "--format", "table {{.Name}}\t{{.Image}}\t{{.State}}\t{{.Status}}")
 		if err != nil {
 			m.logger.Printf("[WARN] Post-start status check failed for %s: %v", name, err)
 			return