Remove RelayHubStatus, NostrFeed, and related composables for codebase cleanup

- Delete RelayHubStatus.vue and its associated components to streamline the application structure.
- Remove NostrFeed.vue to eliminate unused functionality and improve maintainability.
- Eliminate the legacy useRelayHub composable, reflecting a shift towards modular service architecture.
- Clean up router configuration by removing references to deleted components, enhancing clarity and organization.

src/composables/useRelayHub.ts

@@ -1,7 +0,0 @@
-// Legacy composable stub - replaced by modular base module services
-export function useRelayHub() {
-  return {
-    connectedRelays: [],
-    status: 'disconnected'
-  }
-}