fix(topic): correct 'make global' API call and improve UI

- Change 'make global' API method from POST to PUT in AdminView.tsx
- Refine backend update logic for 'isGlobal' to correctly handle boolean values
- Improve 'make global' and 'private' UI with icons and better styling in AdminView.tsx and TopicsView.tsx

apps/server/src/api.ts

@@ -180,7 +180,7 @@ api.put(
 			.update(topics)
 			.set({
 				...body,
-				isGlobal: body.isGlobal ?? (undefined as any),
+				isGlobal: body.isGlobal !== undefined ? body.isGlobal : undefined,
 			})
 			.where(eq(topics.id, id))
 			.returning();