fix(go): add timestamp field to WS broadcast packet — fixes #172

The Go server's WebSocket broadcast included first_seen but not
timestamp in the nested packet object. The frontend packets.js
filters on m.data.packet and reads p.timestamp for row insertion
and sorting. Without this field, live-updating silently failed
(rows inserted with undefined latest, breaking display).

Mirrors the pattern already used in txToMap() (store.go:1168)
which correctly emits both first_seen and timestamp.

Also updates websocket_test.go to assert timestamp presence
in broadcast data to prevent regression.

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

cmd/server/store.go

@@ -950,6 +950,7 @@ func (s *PacketStore) IngestNewFromDB(sinceID, limit int) ([]map[string]interfac
 			"raw_hex":           strOrNil(tx.RawHex),
 			"hash":              strOrNil(tx.Hash),
 			"first_seen":        strOrNil(tx.FirstSeen),
+			"timestamp":         strOrNil(tx.FirstSeen),
 			"route_type":        intPtrOrNil(tx.RouteType),
 			"payload_type":      intPtrOrNil(tx.PayloadType),
 			"decoded_json":      strOrNil(tx.DecodedJSON),

cmd/server/websocket_test.go

@@ -234,8 +234,8 @@ func TestPollerBroadcastsNewData(t *testing.T) {
 		if !ok {
 			t.Fatal("expected data.packet to be an object")
 		}
-		// Verify key fields exist in nested packet
-		for _, field := range []string{"id", "hash", "payload_type"} {
+		// Verify key fields exist in nested packet (timestamp required by packets.js)
+		for _, field := range []string{"id", "hash", "payload_type", "timestamp"} {
 			if _, exists := pktMap[field]; !exists {
 				t.Errorf("expected data.packet.%s to exist", field)
 			}