Fix TypeScript errors in auctions, dashboard, and api

- Made Auction.valuation optional (API doesn't always return it)
- Fixed domain.notify to domain.notify_on_available in dashboard
- Changed api.request from private to protected for inheritance

frontend/src/app/auctions/page.tsx

@@ -49,7 +49,7 @@ interface Auction {
   age_years: number | null
   tld: string
   affiliate_url: string
-  valuation: AuctionValuation | null
+  valuation?: AuctionValuation | null
 }
 
 interface Opportunity {

frontend/src/app/dashboard/page.tsx

@@ -682,17 +682,17 @@ export default function DashboardPage() {
                                   <Sparkles className="w-4 h-4" />
                                 </button>
                                 <button
-                                  onClick={() => handleToggleNotify(domain.id, domain.notify)}
+                                  onClick={() => handleToggleNotify(domain.id, domain.notify_on_available)}
                                   disabled={togglingNotifyId === domain.id}
                                   className={clsx(
                                     "p-2 rounded-lg transition-all",
-                                    domain.notify 
+                                    domain.notify_on_available 
                                       ? "text-accent hover:text-accent-hover hover:bg-accent-muted" 
                                       : "text-foreground-subtle hover:text-foreground hover:bg-background-tertiary"
                                   )}
-                                  title={domain.notify ? "Notifications on" : "Notifications off"}
+                                  title={domain.notify_on_available ? "Notifications on" : "Notifications off"}
                                 >
-                                  <Bell className={clsx("w-4 h-4", domain.notify && "fill-current", togglingNotifyId === domain.id && "animate-pulse")} />
+                                  <Bell className={clsx("w-4 h-4", domain.notify_on_available && "fill-current", togglingNotifyId === domain.id && "animate-pulse")} />
                                 </button>
                                 <button
                                   onClick={() => handleRefresh(domain.id)}

frontend/src/lib/api.ts

@@ -40,7 +40,7 @@ class ApiClient {
     return this.token
   }
 
-  private async request<T>(
+  protected async request<T>(
     endpoint: string,
     options: RequestInit = {}
   ): Promise<T> {