Introduce watchdog and serialization improvements

- Added watchdog timer for improved system stability and responsiveness.
- Switched save data serialization to Bincode for better efficiency.
- Enhanced compatibility by supporting fallback to older JSON format.
- Improved logging during flash operations for easier debugging.
- Simplified SavegameManager by managing storage directly.

Software/MainBoard/rust/.idea/vcs.xml

@@ -2,5 +2,6 @@
 <project version="4">
   <component name="VcsDirectoryMappings">
     <mapping directory="$PROJECT_DIR$/../../.." vcs="Git" />
+    <mapping directory="$PROJECT_DIR$/../../../website/themes/blowfish" vcs="Git" />
   </component>
 </project>