feat(FN-4078): add ntfy access token support to notifications

Adds ntfy access token support to Fusion's notification system, wiring the token through the core settings schema, dashboard UI (SettingsModal), engine notifier, and notification pipeline, with corresponding tests across core, dashboard, and engine packages; also updates settings and storage documen

Fusion-Task-Id: FN-4078

packages/dashboard/app/api/legacy.ts

@@ -993,7 +993,15 @@ export function testNotification(providerId: string, config?: Record<string, unk
  * Backward-compatible ntfy test helper.
  * Wraps testNotification() while preserving the legacy function signature.
  */
-export function testNtfyNotification(config?: { ntfyEnabled?: boolean; ntfyTopic?: string; ntfyBaseUrl?: string }, projectId?: string): Promise<{ success: boolean }> {
+export function testNtfyNotification(
+  config?: {
+    ntfyEnabled?: boolean;
+    ntfyTopic?: string;
+    ntfyBaseUrl?: string;
+    ntfyAccessToken?: string;
+  },
+  projectId?: string,
+): Promise<{ success: boolean }> {
   return testNotification("ntfy", config as Record<string, unknown> | undefined, projectId);
 }