feat(mesh-ui): render tx/lightning relay typed messages and skip self-send

Adds renderers for tx_relay, tx_relay_response, tx_confirmation,
lightning_relay, and lightning_relay_response message types so these
appear as rich cards in the chat stream. sendArchMessage now looks up
our own onion via getTorAddress and skips federation peers that match,
preventing the duplicate "echoed back to self" message we were seeing
on single-node test federations. Empty-federation error message is
also clearer.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

neode-ui/src/stores/mesh.ts

@@ -42,6 +42,11 @@ export type MeshMessageTypeLabel =
   | 'psbt_hash'
   | 'coordinate'
   | 'block_header'
+  | 'tx_relay'
+  | 'tx_relay_response'
+  | 'tx_confirmation'
+  | 'lightning_relay'
+  | 'lightning_relay_response'
 
 export interface MeshMessage {
   id: number