fix: add missing pinned/starred fields to in-memory-feed-adapter

The FeedItemSchema requires pinned and starred boolean fields, but the
in-memory-feed-adapter was not including them when constructing new
FeedItem objects, causing the DTS build to fail with TS2739.

Co-authored-by: hotlong <50353452+hotlong@users.noreply.github.com>

Author: Copilot

packages/services/service-feed/src/in-memory-feed-adapter.ts

@@ -147,6 +147,8 @@ export class InMemoryFeedAdapter implements IFeedService {
       visibility: input.visibility ?? 'public',
       replyCount: 0,
       isEdited: false,
+      pinned: false,
+      starred: false,
       createdAt: now,
     };