fix: implement proper NIP-51 bookmark fetching from nostr relays

- Add RelayPool to connect to nostr relays (damus.io, nos.lol, snort.social)
- Fix bookmark fetching to actually query relays instead of empty local store
- Use eventStore.filters() with Observable subscription to fetch kind 10003 events
- Add proper RxJS imports for takeUntil and timer
- Implement 5-second timeout for relay queries
- Add applesauce-relay dependency for relay connectivity
- Fix critical bug where bookmarks were never fetched from network

This ensures we're actually displaying kind:10003 bookmark events from the
logged-in user as specified in NIP-51, not just querying an empty local store.

node_modules/.package-lock.json

@@ -1943,6 +1943,23 @@
         "url": "lightning:nostrudel@geyser.fund"
       }
     },
+    "node_modules/applesauce-relay": {
+      "version": "3.1.0",
+      "resolved": "https://registry.npmjs.org/applesauce-relay/-/applesauce-relay-3.1.0.tgz",
+      "integrity": "sha512-YseV51O3pc9IIX9MoP4XrVmkUq6a0u8h7n/B4zg0Y3bCQEs415LbM3UwIwZzF1DAEnphOu2xXgkH/9QCg5HvFg==",
+      "license": "MIT",
+      "dependencies": {
+        "@noble/hashes": "^1.7.1",
+        "applesauce-core": "^3.1.0",
+        "nanoid": "^5.0.9",
+        "nostr-tools": "~2.15",
+        "rxjs": "^7.8.1"
+      },
+      "funding": {
+        "type": "lightning",
+        "url": "lightning:nostrudel@geyser.fund"
+      }
+    },
     "node_modules/applesauce-signers": {
       "version": "3.1.0",
       "resolved": "https://registry.npmjs.org/applesauce-signers/-/applesauce-signers-3.1.0.tgz",