feat(clients): bulk-set XTLS flow from the Adjust dialog (#5524)

* feat(clients): bulk-set XTLS flow from the Adjust dialog

Add a "Set flow" dropdown to the bulk Adjust dialog so an admin can set or
clear the XTLS flow on all selected clients at once, alongside the existing
days/traffic bumps. Empty by default (no effect on save); "Disable" clears
flow, and the two vision values mirror the per-client credential tab.

Flow rides the existing inbound-JSON -> SyncInbound path (ClientRecord.Flow +
client_inbounds.flow_override), so no new endpoint, DB column, or migration.
Setting a vision flow is gated by inboundCanEnableTlsFlow: ineligible inbounds
are left untouched and reported as skipped; clearing is always allowed. A real
flow change requests an xray restart (local) or a node reconcile (remote).

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

* fix(clients): keep days/traffic write when bulk flow is ineligible

Address review on the bulk-flow-adjust PR:

- Blocking: a client adjusted with both a days/traffic delta and a flow
  directive on a flow-ineligible inbound had the flow-ineligibility recorded
  into the same skip set that gates the ClientTraffic write, so the inbound
  JSON / ClientRecord advanced but ClientTraffic did not — divergent stores,
  and the client misreported as skipped. Track flow ineligibility in its own
  map (bulkInboundAdjustResult.flowIneligible) so it only feeds the final
  Skipped report and never suppresses the expiry/total persistence.
- Drop the broad delete(skippedReasons, email): flow reasons no longer enter
  skippedReasons, so honoring a flow can no longer erase an unrelated skip
  reason (unlimited expiry, a real persistence error on another inbound).
- Drop the inline comment block from ClientBulkAdjustModal.tsx (file had none);
  move the whitelist-sync note next to bulkFlowAllowed, the source of truth.
- Document the optional flow field in the bulkAdjust API-docs example
  (endpoints.ts) and regenerate openapi.json.
- Add a regression test covering days+flow on an ineligible inbound.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

---------

Co-authored-by: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

internal/web/translation/en-US.json

@@ -831,9 +831,12 @@
       "bulkDeleteConfirmContent": "Each selected client is removed from every attached inbound and its traffic record is dropped. This cannot be undone.",
       "bulkAdjustTitle": "Adjust {count} clients",
       "bulkAdjustHint": "Positive values extend, negative values reduce. Clients with unlimited expiry or traffic are skipped for that field.",
-      "bulkAdjustNothing": "Set days or traffic before applying.",
+      "bulkAdjustNothing": "Set days, traffic, or flow before applying.",
       "addDays": "Add days",
       "addTrafficGB": "Add traffic (GB)",
+      "bulkFlow": "Set flow",
+      "bulkFlowNoChange": "No change",
+      "bulkFlowDisable": "Disable (clear flow)",
       "delDepleted": "Delete depleted",
       "delDepletedConfirmTitle": "Delete depleted clients?",
       "delDepletedConfirmContent": "Removes every client whose traffic quota is exhausted or whose expiry has passed. This cannot be undone.",