feat(sub): expose last subscription fetch time (#6217)

* feat(sub): expose last subscription fetch time

Record successful GET subscription fetches per client and surface the timestamp in the client API and UI.

* fix(frontend): include last subscription fetch in client traffic

* Update sub_fetch_test.go

---------

Co-authored-by: Hermes Agent <hermes-agent@localhost>

frontend/src/generated/examples.ts

@@ -305,6 +305,7 @@ export const EXAMPLES: Record<string, unknown> = {
     "id": 14825,
     "inboundId": 1,
     "lastOnline": 1735680000000,
+    "lastSubFetch": 1735680000000,
     "reset": 0,
     "subId": "i7tvdpeffi0hvvf1",
     "total": 10737418240,
@@ -422,6 +423,7 @@ export const EXAMPLES: Record<string, unknown> = {
         "id": 14825,
         "inboundId": 1,
         "lastOnline": 1735680000000,
+        "lastSubFetch": 1735680000000,
         "reset": 0,
         "subId": "i7tvdpeffi0hvvf1",
         "total": 10737418240,

frontend/src/generated/schemas.ts

@@ -1298,6 +1298,11 @@ export const SCHEMAS: Record<string, unknown> = {
         "format": "int64",
         "type": "integer"
       },
+      "lastSubFetch": {
+        "example": 1735680000000,
+        "format": "int64",
+        "type": "integer"
+      },
       "reset": {
         "example": 0,
         "type": "integer"
@@ -1329,6 +1334,7 @@ export const SCHEMAS: Record<string, unknown> = {
       "id",
       "inboundId",
       "lastOnline",
+      "lastSubFetch",
       "reset",
       "subId",
       "total",

frontend/src/generated/types.ts

@@ -318,6 +318,7 @@ export interface ClientTraffic {
   id: number;
   inboundId: number;
   lastOnline: number;
+  lastSubFetch: number;
   reset: number;
   subId: string;
   total: number;

frontend/src/generated/zod.ts

@@ -340,6 +340,7 @@ export const ClientTrafficSchema = z.object({
   id: z.number().int(),
   inboundId: z.number().int(),
   lastOnline: z.number().int(),
+  lastSubFetch: z.number().int(),
   reset: z.number().int(),
   subId: z.string(),
   total: z.number().int(),