feat(sub): add per-client subscription HWID limits (#5802)

* feat(sub): add per-client subscription HWID limits

* fix(sub): address HWID review on shared subId and bulk create

* fix(sub): store HWID devices by sub_id and drop anchor client workaround

* fix(sub): restore UA auto-detect and HTML page routing in subs()

The cherry-pick of the HWID gate onto main's refactored SUBController
had dropped main's UA-based format auto-detection and sub-page handling
from subs(). Restore those branches, slotting enforceHwid after the
HTML page and before format detection so the gate only applies to
machine-readable subscription bodies.

Also adapt tests to main's options-struct constructor and to the
ClientService.Update signature extended with limitHwid.

* fix(frontend): drop axios from HttpUtil.delete

The bulk-delete rework's committed version still referenced axios,
which this file no longer imports, breaking typecheck in CI. Use the
httpRequest wrapper like the other verbs.

---------

Co-authored-by: Sanaei <ho3ein.sanaei@gmail.com>

internal/web/service/client_stat_reuse_test.go

@@ -43,7 +43,7 @@ func TestAddClientStat_RefreshesStaleRowOnInboundDeleteThenReuse(t *testing.T) {
 	if _, err := svc.Update(inboundSvc, rec0.Id, model.Client{
 		Email: email, SubID: subID, Enable: false,
 		TotalGB: 0, ExpiryTime: 1000, Reset: 0,
-	}); err != nil {
+	}, 0); err != nil {
 		t.Fatalf("Update to disabled: %v", err)
 	}