v0.4.6: MariaDB validation fix + dashboard deployed-only + protected stack restart

- Fix ValidateDump() to scan first 10 lines for header (MariaDB 11.4+ sandbox comment)
- Dashboard shows only deployed/protected stacks, heading "Telepített alkalmazások"
- Protected stacks show restart button when operational (both dashboard + stacks page)
- API blocks all actions except restart on protected stacks
- docker-setup.sh creates .felhom.yml for FileBrowser (subdomain: files)

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

controller/internal/backup/dbdump.go

@@ -264,18 +264,38 @@ func ValidateDump(filePath string, dbType DBType) DumpValidation {
 	}
 	v.TableCount = tableCount
 
-	// Basic header check
-	switch dbType {
-	case DBTypePostgres:
-		if !strings.HasPrefix(content, "--") {
-			v.Error = "PostgreSQL dump missing comment header"
-			return v
+	// Header check — scan first 10 lines for expected dump header
+	// MariaDB 11.4+ prepends a sandbox comment before the header line
+	headerFound := false
+	lines := strings.SplitN(content, "\n", 11) // at most 11 parts = 10 lines
+	for i, line := range lines {
+		if i >= 10 {
+			break
 		}
-	case DBTypeMariaDB:
-		if !strings.HasPrefix(content, "-- ") {
+		switch dbType {
+		case DBTypeMariaDB:
+			if strings.HasPrefix(line, "-- MariaDB dump") ||
+				strings.HasPrefix(line, "-- MySQL dump") ||
+				strings.HasPrefix(line, "-- mysqldump") {
+				headerFound = true
+			}
+		case DBTypePostgres:
+			if strings.HasPrefix(line, "-- PostgreSQL database dump") {
+				headerFound = true
+			}
+		}
+		if headerFound {
+			break
+		}
+	}
+	if !headerFound {
+		switch dbType {
+		case DBTypeMariaDB:
 			v.Error = "MariaDB dump missing comment header"
-			return v
+		case DBTypePostgres:
+			v.Error = "PostgreSQL dump missing comment header"
 		}
+		return v
 	}
 
 	if tableCount == 0 {