feat(agent v0.1.6): métriques réseau enrichies + hardware dmidecode

- Nouveaux types payload: NetworkInterface, HardwareInfo
- Config: slow_daily_time (HH:MM), network_info, hardware_info
- Module network_info: interfaces locales, type ETH/WIFI, speed, MAC, WoL, iperf3
- Module hardware: dmidecode (carte mère, CPU, slots RAM, type/vitesse)
- Scheduler: collecte au démarrage + 1×/jour à l'heure configurée
- install.sh: ajout iperf3, dmidecode dans paquets

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

agent/src/config.rs

@@ -90,6 +90,26 @@ pub struct MetricsConfig {
     pub temperature: MetricProto,
     #[serde(default)]
     pub smart: MetricProto,
+    #[serde(default)]
+    pub network_info: SlowMetricProto,
+    #[serde(default)]
+    pub hardware_info: SlowMetricProto,
+    #[serde(default = "default_slow_time")]
+    pub slow_daily_time: String,
+}
+
+fn default_slow_time() -> String { "03:00".to_string() }
+
+#[derive(Deserialize, Debug, Clone)]
+pub struct SlowMetricProto {
+    #[serde(default = "default_true")]
+    pub udp: bool,
+    #[serde(default)]
+    pub mqtt: bool,
+}
+
+impl Default for SlowMetricProto {
+    fn default() -> Self { Self { udp: true, mqtt: false } }
 }
 
 #[derive(Deserialize, Debug, Clone, Default)]