feat(nostr): Implement Nostr Feed with real-time note fetching

- Add NostrFeed component to display Nostr network notes
- Integrate date-fns for human-readable timestamp formatting
- Enhance NostrClient with fetchNotes and subscribeToNotes methods
- Implement loading, error, and empty state handling
- Add scrollable card-based UI for note display
- Configure dynamic relay selection with fallback to environment variables

package-lock.json

@@ -13,6 +13,7 @@
         "@vueuse/head": "^2.0.0",
         "class-variance-authority": "^0.7.1",
         "clsx": "^2.1.1",
+        "date-fns": "^4.1.0",
         "fuse.js": "^7.0.0",
         "lucide-vue-next": "^0.474.0",
         "nostr-tools": "^2.10.4",
@@ -4338,6 +4339,16 @@
         "url": "https://github.com/sponsors/ljharb"
       }
     },
+    "node_modules/date-fns": {
+      "version": "4.1.0",
+      "resolved": "https://registry.npmjs.org/date-fns/-/date-fns-4.1.0.tgz",
+      "integrity": "sha512-Ukq0owbQXxa/U3EGtsdVBkR1w7KOQ5gIBqdH2hkvknzZPYvBxb/aa6E8L7tmjFtkwZBu3UXBbjIgPo/Ez4xaNg==",
+      "license": "MIT",
+      "funding": {
+        "type": "github",
+        "url": "https://github.com/sponsors/kossnocorp"
+      }
+    },
     "node_modules/de-indent": {
       "version": "1.0.2",
       "resolved": "https://registry.npmjs.org/de-indent/-/de-indent-1.0.2.tgz",