feat: configuration platformio + parametrage initial

- Ajout des dépendances libs (ESPAsyncWebServer, AsyncTCP, OneWire, DallasTemperature, PubSubClient, ArduinoJson)
- Configuration LittleFS pour le système de fichiers
- Ajout des flags de compilation et d'upload (auth=Jardin2026)
- Création de parametrage.md contenant les paramètres initiaux des sondes, WiFi et MQTT

Compilation : SUCCESS (955692 bytes en Flash, 45560 bytes en RAM utilisés)

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

platformio.ini

@@ -1,14 +1,16 @@
 ; PlatformIO Project Configuration File
-;
-;   Build options: build flags, source filter
-;   Upload options: custom upload port, speed and extra flags
-;   Library options: dependencies, extra library storages
-;   Advanced options: extra scripting
-;
-; Please visit documentation for the other options and examples
-; https://docs.platformio.org/page/projectconf.html
-
 [env:esp32dev]
 platform = espressif32
 board = esp32dev
 framework = arduino
+board_build.filesystem = littlefs
+
+lib_deps =
+    esp32async/ESPAsyncWebServer
+    esp32async/AsyncTCP
+    paulstoffregen/OneWire @ ^2.3.7
+    milesburton/DallasTemperature @ ^3.11.0
+    knolleary/PubSubClient @ ^2.8
+    bblanchon/ArduinoJson @ ^7
+
+upload_flags = --auth=Jardin2026