feat: complete Phase 2 network features for spellbooks

Sharing Enhancements:
- Install qrcode library for QR code generation
- Create ShareSpellbookDialog with tabbed interface
- Support multiple share formats: Web URL, naddr, nevent
- QR code generation and download for each format
- Quick copy buttons with visual feedback
- Integrated into SpellbookDetailRenderer

Network Discovery:
- Add "Discover" filter to browse spellbooks from other users
- Query AGGREGATOR_RELAYS for network spellbook discovery
- Show author names using UserName component
- Conditional UI: hide owner actions for discovered spellbooks
- Support viewing and applying layouts from the community

Preview Route Polish:
- Loading states with spinner during NIP-05 resolution
- 10-second timeout for NIP-05 resolution
- Error banners for resolution failures
- Author name and creation date in preview banner
- Copy link button in preview mode

Conflict Resolution:
- compareSpellbookVersions() function in spellbook-manager
- ConflictResolutionDialog component for version conflicts
- Side-by-side comparison of local vs network versions
- Show workspace/window counts and timestamps

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

src/services/hub.ts

@@ -5,6 +5,7 @@ import pool from "./relay-pool";
 import { relayListCache } from "./relay-list-cache";
 import { getSeenRelays } from "applesauce-core/helpers/relays";
 import type { NostrEvent } from "nostr-tools/core";
+import accountManager from "./accounts";
 
 /**
  * Publishes a Nostr event to relays using the author's outbox relays
@@ -25,7 +26,7 @@ async function publishEvent(event: NostrEvent): Promise<void> {
   // If still no relays, throw error
   if (relays.length === 0) {
     throw new Error(
-      "No relays found for publishing. Please configure relay list (kind 10002) or ensure event has relay hints."
+      "No relays found for publishing. Please configure relay list (kind 10002) or ensure event has relay hints.",
     );
   }
 
@@ -36,6 +37,8 @@ async function publishEvent(event: NostrEvent): Promise<void> {
   eventStore.add(event);
 }
 
+const factory = new EventFactory();
+
 /**
  * Global action hub for Grimoire
  * Used to register and execute actions throughout the application
@@ -45,4 +48,10 @@ async function publishEvent(event: NostrEvent): Promise<void> {
  * - EventFactory: Creates and signs events
  * - publishEvent: Publishes events to author's outbox relays (with fallback to seen relays)
  */
-export const hub = new ActionHub(eventStore, new EventFactory(), publishEvent);
+export const hub = new ActionHub(eventStore, factory, publishEvent);
+
+// Sync factory signer with active account
+// This ensures the hub can sign events when an account is active
+accountManager.active$.subscribe((account) => {
+  factory.setSigner(account?.signer || undefined);
+});