Add mcutie MQTT client implementation and improve library structure

- Integrated `mcutie` library as a core MQTT client for device communication.
- Added support for Home Assistant entities (binary sensor, button) via MQTT.
- Implemented buffer management, async operations, and packet encoding/decoding.
- Introduced structured error handling and device registration features.
- Updated `Cargo.toml` with new dependencies and enabled feature flags for `serde` and `log`.
- Enhanced logging macros with configurable options (`defmt` or `log`).
- Organized codebase into modules (buffer, components, IO, publish, etc.) for better maintainability.

fix legacy dependecencies and compatiblity with mcutie vendored lib

fix shit i hate this

rust/src/webserver/get_json.rs

@@ -139,7 +139,7 @@ pub(crate) async fn get_time<T, const N: usize>(
 ) -> FatResult<Option<String>> {
     let mut board = BOARD_ACCESS.get().await.lock().await;
     let conf = board.board_hal.get_config();
-    let tz = Tz::from_str(conf.timezone.as_ref().unwrap().as_str()).unwrap();
+    let tz = Tz::from_str(conf.timezone.as_ref().unwrap_or(&"Europe/Berlin".to_string()).as_str()).unwrap();
     let native = esp_time().await.with_timezone(&tz).to_rfc3339();
 
     let rtc = match board.board_hal.get_rtc_module().get_rtc_time().await {