feat(nodes): add distinct purple indicator when panel is online but Xray core failed (#5040)

* feat(nodes): add distinct purple indicator when panel is online but Xray core failed

Currently nodes only show binary online/offline based on panel API reachability.

This adds a third state:
- Green: panel reachable + Xray healthy
- Purple pulsing dot + "Online (Xray Error)": panel API works (management actions still available) but the node Xray process is in error or stopped. Tooltip shows the remote xrayError.
- Red: unreachable (unchanged)

Backend now captures xray.state + xray.errorMsg from /panel/api/server/status heartbeats and probes.
New fields on Node + NodeSummary, forwarded for transitive nodes.
Frontend Zod + NodeList rendering + dedicated .xray-error-dot CSS (color #722ED1) + i18n key.

Color chosen purple per feedback after initial implementation.

Refs: worktree xray-failed-in-nodes

* fix: remove invalid JSON comment causing CI failures

* chore: regenerate OpenAPI schemas and types for xray error indicators

* chore: regenerate examples and schemas for xray error indicators

* chore: regenerate missing openapi.json examples

* fix

---------

Co-authored-by: Rqzbeh <rqzbeh@users.noreply.github.com>
Co-authored-by: Sanaei <ho3ein.sanaei@gmail.com>

web/translation/ru-RU.json

@@ -896,7 +896,9 @@
       "statusValues": {
         "online": "В сети",
         "offline": "Не в сети",
-        "unknown": "Неизвестно"
+        "unknown": "Неизвестно",
+        "xrayError": "Ошибка Xray",
+        "xrayStopped": "Остановлен"
       },
       "toasts": {
         "list": "Не удалось загрузить узлы",