Migrate serialization from Bincode to Postcard

- Replaced Bincode with Postcard for serialization/deserialization across configs and save operations.
- Simplified struct derives by removing `bincode`-specific traits.
- Updated `Cargo.toml` and `Cargo.lock` to include `postcard` and dependencies.
- Added padding stripping for deserialization and improved error handling.
- Adjusted serialization logic in `savegame_manager.rs` and related modules.

Software/MainBoard/rust/src/hal/v4_hal.rs

@@ -12,7 +12,6 @@ use crate::log::{log, LogMessage};
 use alloc::boxed::Box;
 use alloc::string::ToString;
 use async_trait::async_trait;
-use bincode::config;
 use canapi::id::{classify, plant_id, MessageKind, IDENTIFY_CMD_OFFSET};
 use canapi::SensorSlot;
 use chrono::{DateTime, FixedOffset, Utc};
@@ -36,7 +35,6 @@ use measurements::{Current, Voltage};
 use pca9535::{GPIOBank, Pca9535Immediate, StandardExpanderInterface};
 
 pub const BACKUP_HEADER_MAX_SIZE: usize = 64;
-const CONFIG: config::Configuration = config::standard();
 
 const MPPT_CURRENT_SHUNT_OHMS: f64 = 0.05_f64;
 const TWAI_BAUDRATE: twai::BaudRate = twai::BaudRate::Custom(twai::TimingConfig {
@@ -543,7 +541,7 @@ impl<'a> BoardInteraction<'a> for V4<'a> {
     }
     async fn backup_config(&mut self, controller_config: &PlantControllerConfig) -> FatResult<()> {
         let mut buffer: [u8; 4096 - BACKUP_HEADER_MAX_SIZE] = [0; 4096 - BACKUP_HEADER_MAX_SIZE];
-        let length = bincode::encode_into_slice(controller_config, &mut buffer, CONFIG)?;
+        let length = postcard::to_slice(controller_config, &mut buffer)?.len();
         info!("Writing backup config of size {}", length);
         let mut checksum = X25.digest();
         checksum.update(&buffer[..length]);
@@ -556,7 +554,7 @@ impl<'a> BoardInteraction<'a> for V4<'a> {
             size: length as u16,
         };
         info!("Header is {:?}", header);
-        bincode::encode_into_slice(&header, &mut header_page_buffer, CONFIG)?;
+        postcard::to_slice(&header, &mut header_page_buffer)?;
         info!("Header is serialized");
         self.get_rtc_module().write(0, &header_page_buffer)?;
         info!("Header written");
@@ -600,7 +598,7 @@ impl<'a> BoardInteraction<'a> for V4<'a> {
             bail!("CRC mismatch in backup data")
         }
         info!("CRC is correct");
-        let (decoded, _) = bincode::decode_from_slice(&store[..], CONFIG)?;
+        let decoded = postcard::from_bytes(&store[..])?;
         info!("Backup data decoded");
         Ok(decoded)
     }
@@ -609,8 +607,7 @@ impl<'a> BoardInteraction<'a> for V4<'a> {
         let mut header_page_buffer = [0_u8; BACKUP_HEADER_MAX_SIZE];
         self.get_rtc_module().read(0, &mut header_page_buffer)?;
         info!("Read header page");
-        let info: Result<(BackupHeader, usize), bincode::error::DecodeError> =
-            bincode::decode_from_slice(&header_page_buffer[..], CONFIG);
+        let info = postcard::take_from_bytes::<BackupHeader>(&header_page_buffer[..]);
         info!("decoding header: {:?}", info);
         let (header, _) = info.context("Could not read backup header")?;
         Ok(header)