Initial commit — KC868-A2 contrôleur solaire ESP32

Fonctionnalités :
- Lecture RS485 Modbus Epever Tracer 4210N (115200 bps, FC03/FC04/FC16)
- Moteur de règles JSON (LittleFS) — commande automatique des relais
- Interface web mobile-first (dashboard, règles, config, historique, EPEVER, debug)
- WiFi AP+STA simultanés avec reconnexion automatique et portail captif
- mDNS configurable (pv.local par défaut)
- Configuration registres EPEVER depuis l'UI (18 registres holding)
- Historique basse/haute résolution avec graphes canvas
- VPN WireGuard optionnel (désactivé par défaut, config via UI)
- OTA firmware + filesystem via ElegantOTA
- Deep sleep / économie d'énergie

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

lib/README

@@ -0,0 +1,46 @@
+
+This directory is intended for project specific (private) libraries.
+PlatformIO will compile them to static libraries and link into the executable file.
+
+The source code of each library should be placed in a separate directory
+("lib/your_library_name/[Code]").
+
+For example, see the structure of the following example libraries `Foo` and `Bar`:
+
+|--lib
+|  |
+|  |--Bar
+|  |  |--docs
+|  |  |--examples
+|  |  |--src
+|  |     |- Bar.c
+|  |     |- Bar.h
+|  |  |- library.json (optional. for custom build options, etc) https://docs.platformio.org/page/librarymanager/config.html
+|  |
+|  |--Foo
+|  |  |- Foo.c
+|  |  |- Foo.h
+|  |
+|  |- README --> THIS FILE
+|
+|- platformio.ini
+|--src
+   |- main.c
+
+Example contents of `src/main.c` using Foo and Bar:
+```
+#include <Foo.h>
+#include <Bar.h>
+
+int main (void)
+{
+  ...
+}
+
+```
+
+The PlatformIO Library Dependency Finder will find automatically dependent
+libraries by scanning project source files.
+
+More information about PlatformIO Library Dependency Finder
+- https://docs.platformio.org/page/librarymanager/ldf.html