Refactor OTA update handling and improve error reporting.

Added a CRC check to firmware uploads, streamlined OTA partition management, and replaced detailed slot states with a single unified state representation. Improved consistency in variable formatting, error handling, and code readability across multiple modules.

Software/MainBoard/rust/src_webpack/src/toast.ts

@@ -3,7 +3,7 @@ class ToastService {
     private stylesInjected = false;
 
     constructor() {
-    this.container = this.ensureContainer();
+        this.container = document.getElementById('toast-container') as HTMLElement;
         this.injectStyles();
     }
 
@@ -41,16 +41,6 @@ class ToastService {
         return div;
     }
 
-  private ensureContainer(): HTMLElement {
-    let container = document.getElementById('toast-container');
-    if (!container) {
-      container = document.createElement('div');
-      container.id = 'toast-container';
-      document.body.appendChild(container);
-    }
-    return container;
-  }
-
     private injectStyles() {
         if (this.stylesInjected) return;
         const style = document.createElement('style');