Store chat messages locally for sender and recipient

Messages sent to remote users are now stored locally for the sender, and incoming remote messages are stored for the recipient, ensuring both parties see their message history in the UI. The implementation creates or updates conversations as needed and marks messages as delivered when appropriate.

src/app/api/swarm/chat/inbox/route.ts

@@ -50,8 +50,8 @@ export async function POST(request: NextRequest) {
         return NextResponse.json({ error: 'Recipient not found' }, { status: 404 });
       }
 
-      // Import chatInbox schema
-      const { chatInbox } = await import('@/db/schema');
+      // Import schemas
+      const { chatInbox, chatConversations, chatMessages } = await import('@/db/schema');
       
       // Store in V2 inbox
       await db.insert(chatInbox).values({
@@ -62,7 +62,54 @@ export async function POST(request: NextRequest) {
         expiresAt: new Date(Date.now() + 30 * 24 * 60 * 60 * 1000)
       });
 
-      console.log(`[Swarm Chat V2] Received encrypted message for ${recipientDid}`);
+      // Also create conversation and message for recipient UI
+      // Extract sender info from envelope
+      const senderHandle = body.handle || body.did; // Fallback to DID if no handle
+      const senderFullHandle = `${senderHandle}@${body.did?.split(':')[2] || 'unknown'}`; // Extract domain from DID
+      
+      // Get or create conversation for recipient
+      let conversation = await db.query.chatConversations.findFirst({
+        where: and(
+          eq(chatConversations.participant1Id, recipient.id),
+          eq(chatConversations.participant2Handle, senderFullHandle)
+        )
+      });
+
+      if (!conversation) {
+        const [newConv] = await db.insert(chatConversations).values({
+          participant1Id: recipient.id,
+          participant2Handle: senderFullHandle,
+          lastMessageAt: new Date(),
+          lastMessagePreview: '[Encrypted message]'
+        }).returning();
+        conversation = newConv;
+        console.log(`[Swarm Chat V2] Created conversation for recipient:`, conversation.id);
+      } else {
+        // Update last message time
+        await db.update(chatConversations)
+          .set({ 
+            lastMessageAt: new Date(),
+            lastMessagePreview: '[Encrypted message]'
+          })
+          .where(eq(chatConversations.id, conversation.id));
+      }
+
+      // Store message reference so it appears in UI
+      const messageId = crypto.randomUUID();
+      await db.insert(chatMessages).values({
+        conversationId: conversation.id,
+        senderHandle: senderFullHandle,
+        senderDisplayName: null, // Unknown until decrypted
+        senderAvatarUrl: null,
+        senderNodeDomain: body.did?.split(':')[2] || null,
+        encryptedContent: ciphertext,
+        senderChatPublicKey: null,
+        swarmMessageId: `swarm:v2:${messageId}`,
+        deliveredAt: new Date(),
+        readAt: null,
+      });
+
+      console.log(`[Swarm Chat V2] Received encrypted message for ${recipientDid}, conversation:`, conversation.id);
 
       return NextResponse.json({
         success: true,