fix: resolve NIP-17 crashes and conversation key inconsistencies

Critical Fixes:
1. Fixed crashes from non-DM gift wraps (reactions, private relays, etc.)
   - Only use getConversationIdentifierFromMessage() for kind 14 DMs
   - Manual conversation key generation for other kinds (7, 25050, etc.)
   - No more "Can only get participants from direct message event" errors

2. Fixed chat $me (saved messages) not loading any messages
   - Deduplicate pubkeys in getConversationKey() method
   - Self-conversations now correctly map to same key as stored messages
   - Conversation key "user:user" → "user" after deduplication

3. Added participant tooltip for group DMs
   - Shows all participant names when hovering over group title
   - Only displays for groups with 3+ participants
   - Deduplicates participant list properly

Technical Details:
- Kind 14 (DMs): Use applesauce getConversationIdentifierFromMessage()
- Other kinds: Extract p-tags manually and sort
- All conversation keys deduplicated and sorted for consistency
- Matches storage format from gift-wrap service

src/components/ChatViewer.tsx

@@ -940,6 +940,28 @@ export function ChatViewer({
                         {conversation.metadata.description}
                       </p>
                     )}
+                    {/* Participants for NIP-17 group DMs */}
+                    {protocol === "nip-17" &&
+                      conversation.participants.length > 2 && (
+                        <div className="flex flex-col gap-1">
+                          <span className="text-xs text-primary-foreground/80">
+                            Participants:
+                          </span>
+                          <div className="flex flex-col gap-0.5 text-xs">
+                            {[
+                              ...new Set(
+                                conversation.participants.map((p) => p.pubkey),
+                              ),
+                            ].map((participantPubkey) => (
+                              <UserName
+                                key={participantPubkey}
+                                pubkey={participantPubkey}
+                                className="text-xs text-primary-foreground"
+                              />
+                            ))}
+                          </div>
+                        </div>
+                      )}
                     {/* Protocol Type - Clickable */}
                     <div className="flex items-center gap-1.5 text-xs">
                       {(conversation.type === "group" ||

src/lib/chat/adapters/nip-17-adapter.ts

@@ -462,8 +462,9 @@ export class Nip17Adapter extends ChatProtocolAdapter {
    * Helper: Get conversation key from conversation
    */
   private getConversationKey(conversation: Conversation): string {
-    const pubkeys = conversation.participants.map((p) => p.pubkey).sort();
-    return pubkeys.join(":");
+    const pubkeys = conversation.participants.map((p) => p.pubkey);
+    // Deduplicate and sort for consistency with gift wrap storage
+    return [...new Set(pubkeys)].sort().join(":");
   }
 
   /**

src/services/gift-wrap.ts

@@ -775,9 +775,22 @@ class GiftWrapManager {
       throw new Error(`Failed to unlock gift wrap: ${error}`);
     }
 
-    // Use applesauce helper to get the conversation identifier
-    // This properly handles all participants including group DMs
-    const conversationKey = getConversationIdentifierFromMessage(rumor);
+    // Generate conversation key based on rumor kind
+    // For kind 14 (DMs), use applesauce helper which handles groups properly
+    // For other kinds (reactions, etc.), extract participants from p-tags
+    let conversationKey: string;
+    if (rumor.kind === 14) {
+      // Use applesauce helper for DMs - it properly handles group DMs
+      conversationKey = getConversationIdentifierFromMessage(rumor);
+    } else {
+      // For non-DM events (reactions, private relays, etc.),
+      // create conversation key from sender + all p-tags
+      const recipientPubkeys = rumor.tags
+        .filter((t: string[]) => t[0] === "p" && t[1])
+        .map((t: string[]) => t[1]);
+      const allParticipants = [rumor.pubkey, ...recipientPubkeys];
+      conversationKey = [...new Set(allParticipants)].sort().join(":");
+    }
 
     // Get seal ID from gift wrap tags (applesauce stores it there)
     const sealId = rumor.id.split(":")[1] || giftWrap.id;