fix(nip-29): use limit 1 for replaceable participant events

Kinds 39001 and 39002 are replaceable events with d-tag, so there should
only be one valid event of each kind per group. Changed limit from 5 to 1.

src/lib/chat/adapters/nip-29-adapter.ts

@@ -194,13 +194,13 @@ export class Nip29Adapter extends ChatProtocolAdapter {
     const adminsFilter: Filter = {
       kinds: [39001],
       "#d": [groupId],
-      limit: 5, // Should be 1, but allow for duplicates
+      limit: 1,
     };
 
     const membersFilter: Filter = {
       kinds: [39002],
       "#d": [groupId],
-      limit: 5, // Should be 1, but allow for duplicates
+      limit: 1,
     };
 
     // Use pool.request with both filters to fetch and auto-close on EOSE