feat: add SD-backed stats archive and dedicated /stats web console

src/helpers/NetworkService.h

@@ -0,0 +1,50 @@
+#pragma once
+
+#include <Arduino.h>
+#include <helpers/IdentityStore.h>
+#include <helpers/NetworkStateProvider.h>
+
+#if defined(ESP_PLATFORM)
+  #include <WiFi.h>
+#endif
+
+#include "NetworkPrefs.h"
+
+class NetworkService : public NetworkStateProvider {
+public:
+  NetworkService();
+
+  void begin(FILESYSTEM* fs,
+             uint8_t legacy_wifi_powersave = 0,
+             const char* legacy_wifi_ssid = nullptr,
+             const char* legacy_wifi_pwd = nullptr);
+  void end();
+  void loop(bool network_required);
+
+  bool setWifiSSID(const char* ssid);
+  bool setWifiPassword(const char* pwd);
+  const char* getWifiSSID() const { return _prefs.wifi_ssid; }
+  bool setWifiPowerSave(const char* mode);
+  const char* getWifiPowerSave() const;
+  void formatWifiStatusReply(char* reply, size_t reply_size) const;
+  void reconnectWifi();
+
+  bool isWifiConnected() const override;
+  bool hasTimeSync() const override { return _have_time_sync; }
+
+private:
+#if defined(ESP_PLATFORM)
+  static wifi_ps_type_t toEspPowerSave(uint8_t mode);
+  static const char* getPowerSaveLabel(uint8_t mode);
+  void ensureWifi(bool network_required);
+  void updateTimeSync();
+#endif
+  bool savePrefs();
+
+  FILESYSTEM* _fs;
+  NetworkPrefs _prefs;
+  bool _wifi_started;
+  bool _sntp_started;
+  bool _have_time_sync;
+  unsigned long _last_wifi_attempt;
+};