chore: apply code formatting and linting

- format long import statements with consistent line wrapping
- apply consistent indentation across client and server modules
- remove generated tsconfig.tsbuildinfo file

client/src/ui/Toast/toast-context.ts

@@ -0,0 +1,12 @@
+import { createContext } from 'react';
+
+export type ToastVariant = 'success' | 'error' | 'info';
+
+export interface ToastApi {
+  show: (message: string, variant?: ToastVariant) => void;
+  success: (message: string) => void;
+  error: (message: string) => void;
+  info: (message: string) => void;
+}
+
+export const ToastContext = createContext<ToastApi | null>(null);