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>

frontend/src/generated/schemas.ts

@@ -1630,6 +1630,13 @@ export const SCHEMAS: Record<string, unknown> = {
         "example": 86400,
         "type": "integer"
       },
+      "xrayError": {
+        "type": "string"
+      },
+      "xrayState": {
+        "description": "XrayState and XrayError are captured from the remote node's /panel/api/server/status\nduring heartbeats. They let the central panel distinguish \"panel API reachable\"\n(status=online) from \"Xray core itself has failed on the node\" for monitoring.",
+        "type": "string"
+      },
       "xrayVersion": {
         "example": "25.10.31",
         "type": "string"
@@ -1665,6 +1672,8 @@ export const SCHEMAS: Record<string, unknown> = {
       "tlsVerifyMode",
       "updatedAt",
       "uptimeSecs",
+      "xrayError",
+      "xrayState",
       "xrayVersion"
     ],
     "type": "object"
@@ -1726,6 +1735,13 @@ export const SCHEMAS: Record<string, unknown> = {
         "example": 86400,
         "type": "integer"
       },
+      "xrayError": {
+        "type": "string"
+      },
+      "xrayState": {
+        "description": "XrayState/XrayError are populated on successful probes even when the node's\nXray core is not healthy. The UI uses them for a distinct \"panel ok, xray failed\" indicator.",
+        "type": "string"
+      },
       "xrayVersion": {
         "example": "25.10.31",
         "type": "string"
@@ -1739,6 +1755,8 @@ export const SCHEMAS: Record<string, unknown> = {
       "panelVersion",
       "status",
       "uptimeSecs",
+      "xrayError",
+      "xrayState",
       "xrayVersion"
     ],
     "type": "object"