refactor: integrate long-form article rendering into existing reader view

- Create articleService to fetch articles by naddr
- Update Bookmarks component to detect naddr in URL params
- Articles now render in the existing ContentPanel with highlight support
- Remove standalone Article component
- Articles work seamlessly within the existing three-pane layout
- Support for article metadata (title, image, published date, summary)

src/services/articleService.ts

@@ -0,0 +1,102 @@
+import { RelayPool, completeOnEose } from 'applesauce-relay'
+import { lastValueFrom, takeUntil, timer, toArray } from 'rxjs'
+import { nip19 } from 'nostr-tools'
+import { AddressPointer } from 'nostr-tools/nip19'
+import { NostrEvent } from 'nostr-tools'
+import { 
+  getArticleTitle, 
+  getArticleImage, 
+  getArticlePublished, 
+  getArticleSummary 
+} from 'applesauce-core/helpers'
+
+export interface ArticleContent {
+  title: string
+  markdown: string
+  image?: string
+  published?: number
+  summary?: string
+  author: string
+  event: NostrEvent
+}
+
+/**
+ * Fetches a Nostr long-form article (NIP-23) by naddr
+ */
+export async function fetchArticleByNaddr(
+  relayPool: RelayPool,
+  naddr: string
+): Promise<ArticleContent> {
+  try {
+    // Decode the naddr
+    const decoded = nip19.decode(naddr)
+    
+    if (decoded.type !== 'naddr') {
+      throw new Error('Invalid naddr format')
+    }
+
+    const pointer = decoded.data as AddressPointer
+
+    // Define relays to query
+    const relays = pointer.relays && pointer.relays.length > 0 
+      ? pointer.relays 
+      : [
+          'wss://relay.damus.io',
+          'wss://nos.lol',
+          'wss://relay.nostr.band',
+          'wss://relay.primal.net'
+        ]
+
+    // Fetch the article event
+    const filter = {
+      kinds: [pointer.kind],
+      authors: [pointer.pubkey],
+      '#d': [pointer.identifier]
+    }
+
+    // Use applesauce relay pool pattern
+    const events = await lastValueFrom(
+      relayPool
+        .req(relays, filter)
+        .pipe(completeOnEose(), takeUntil(timer(10000)), toArray())
+    )
+
+    if (events.length === 0) {
+      throw new Error('Article not found')
+    }
+
+    // Sort by created_at and take the most recent
+    events.sort((a, b) => b.created_at - a.created_at)
+    const article = events[0]
+
+    const title = getArticleTitle(article) || 'Untitled Article'
+    const image = getArticleImage(article)
+    const published = getArticlePublished(article)
+    const summary = getArticleSummary(article)
+
+    return {
+      title,
+      markdown: article.content,
+      image,
+      published,
+      summary,
+      author: article.pubkey,
+      event: article
+    }
+  } catch (err) {
+    console.error('Failed to fetch article:', err)
+    throw err
+  }
+}
+
+/**
+ * Checks if a string is a valid naddr
+ */
+export function isNaddr(str: string): boolean {
+  try {
+    const decoded = nip19.decode(str)
+    return decoded.type === 'naddr'
+  } catch {
+    return false
+  }
+}