ITEM6 B4: frontend reshaping — xray page retired, stats switches to settings, template read paths closed

- Delete the xray settings page (routes/menu/title), geodata UI/service,
  XraySettingController/Service and routing-sync write paths; the stored
  xrayTemplateConfig row loses its last readers (GetXrayConfigTemplate now
  returns the embedded factory template; B1 already deleted the row).
- Settings GeneralTab gains the four trafficStatsSwitches switches
  (settings.trafficStatsSwitches, B1) with the dual warning copy; entity
  AllSetting carries the key end to end (TestTrafficStatsSwitchesPlumbing).
- Tag-directory consumers (panelOutbound, mtproto egress, node/host
  outbound pickers) move from POST /xray/ to GET /server/outboundDirectory.
- Shared Mux/Sockopt forms and balancer helpers relocated to lib/xray;
  converter preserves sniffing ips/domains exclusions into the panel
  sidecar instead of dropping them (B2 gap closed by retention).
- Freedom final-rules DB fix seeders retired; getDefaultJsonConfig
  endpoint removed (no in-repo consumer); locales pruned to referenced
  keys (pages.xray 331 -> 68) plus the five new settings keys.

internal/web/entity/entity.go

@@ -75,6 +75,12 @@ type AllSetting struct {
 	SubKeyFile                 string `json:"subKeyFile" form:"subKeyFile"`
 	SubUpdates                 int    `json:"subUpdates" form:"subUpdates" validate:"gte=0,lte=525600"`
 	RestartXrayOnClientDisable bool   `json:"restartXrayOnClientDisable" form:"restartXrayOnClientDisable"`
+	// TrafficStatsSwitches (ITEM6 §4.3.1): the whole-network traffic
+	// accounting switches as one JSON string
+	// ({inboundUplink,inboundDownlink,outboundUplink,outboundDownlink}),
+	// carried verbatim so the settings page edits the same key the
+	// sing-box generator reads (settings.trafficStatsSwitches).
+	TrafficStatsSwitches string `json:"trafficStatsSwitches" form:"trafficStatsSwitches"`
 	SubEncrypt                 bool   `json:"subEncrypt" form:"subEncrypt"`
 	SubURI                     string `json:"subURI" form:"subURI"`
 	SubJsonPath                string `json:"subJsonPath" form:"subJsonPath"`