feat(memory): add memory threshold alerts (#5366)

* feat(memory): add memory threshold alerts

Add memory (RAM) threshold alerts following the same architecture as
CPU alerts: CheckMemJob with @every 1m cadence, memoryAlarmWanted gate,
tgMemory/smtpMemory per-subscriber settings (default 80%), EventBusCheckboxes
with inline threshold input, i18n for en-US/ru-RU with English defaults.

# Conflicts:
#	internal/web/translation/ar-EG.json
#	internal/web/translation/es-ES.json
#	internal/web/translation/fa-IR.json
#	internal/web/translation/id-ID.json
#	internal/web/translation/ja-JP.json
#	internal/web/translation/pt-BR.json
#	internal/web/translation/ru-RU.json
#	internal/web/translation/tr-TR.json
#	internal/web/translation/uk-UA.json
#	internal/web/translation/vi-VN.json
#	internal/web/translation/zh-CN.json
#	internal/web/translation/zh-TW.json

* fix: address code review findings for memory alerts

- Remove dead settingService field from CheckMemJob
- Fix cpuThreshold double-emoji in 12 locale files (code prepends 🔴)
- Align TgCpu/TgMemory fields in entity.go
- Add missing SetTgMemory function

* fix: restore settingService in CheckMemJob for consistency with CheckCpuJob

internal/web/service/setting.go

@@ -63,6 +63,7 @@ var defaultValueMap = map[string]string{
 	"tgRunTime":                   "@daily",
 	"tgBotBackup":                 "false",
 	"tgCpu":                       "80",
+	"tgMemory":                    "80",
 	"tgLang":                      "en-US",
 	"twoFactorEnable":             "false",
 	"twoFactorToken":              "",
@@ -131,6 +132,7 @@ var defaultValueMap = map[string]string{
 	"tgEnabledEvents":   "login.attempt,cpu.high",
 	"smtpEnabledEvents": "login.attempt,cpu.high",
 	"smtpCpu":           "80",
+	"smtpMemory":        "80",
 
 	// Email (SMTP) notifications
 	"smtpEnable":         "false",
@@ -531,6 +533,14 @@ func (s *SettingService) GetTgCpu() (int, error) {
 	return s.getInt("tgCpu")
 }
 
+func (s *SettingService) GetTgMemory() (int, error) {
+	return s.getInt("tgMemory")
+}
+
+func (s *SettingService) SetTgMemory(value int) error {
+	return s.setInt("tgMemory", value)
+}
+
 func (s *SettingService) GetTgLang() (string, error) {
 	return s.getString("tgLang")
 }
@@ -1017,6 +1027,14 @@ func (s *SettingService) SetSmtpCpu(value int) error {
 	return s.setInt("smtpCpu", value)
 }
 
+func (s *SettingService) GetSmtpMemory() (int, error) {
+	return s.getInt("smtpMemory")
+}
+
+func (s *SettingService) SetSmtpMemory(value int) error {
+	return s.setInt("smtpMemory", value)
+}
+
 func (s *SettingService) UpdateAllSetting(allSetting *entity.AllSetting) error {
 	if err := s.preserveRedactedSecrets(allSetting); err != nil {
 		return err