feat: filter inbounds and clients by node (#4997)

Multi-node panels had no way to narrow the inbounds or clients lists to
a single node. Add a node filter to both pages:

- Inbounds: a toolbar select (All / Local / each node) that filters the
  list client-side; shown only when the panel has nodes or node-attached
  inbounds.
- Clients: a Nodes multi-select in the filter drawer. Node selections
  are mapped onto inbound IDs client-side and fed through the existing
  inbound CSV paging parameter, so the paging backend is untouched; an
  impossible id (-1) is sent when no inbound matches so the filter
  yields an honest empty result. InboundOption now carries nodeId to
  make the mapping possible.

The local panel is selectable via a 0 sentinel (inbounds without a
nodeId). New i18n keys in all 13 locales.

frontend/src/schemas/client.ts

@@ -44,6 +44,8 @@ export const InboundOptionSchema = z.object({
   port: z.number().optional(),
   tlsFlowCapable: z.boolean().optional(),
   ssMethod: z.string().optional(),
+  // Hosting node id; absent/null for this panel's own inbounds (#4997).
+  nodeId: z.number().nullable().optional(),
 }).loose();
 
 export const InboundOptionsSchema = z.array(InboundOptionSchema);