Fix TypeScript build errors by removing unused imports

- Remove unused PostAdd imports from DashboardLayout and BottomNavigation
- Remove unused Avatar, Chip, Groups imports from SocialContractPage
- Remove unused Divider, FolderShared imports from GroupDetailPage
- Build now passes all TypeScript checks

🤖 Generated with [Claude Code](https://claude.ai/code)

Co-Authored-By: Claude <noreply@anthropic.com>

src/components/layout/DashboardLayout.tsx

@@ -30,7 +30,6 @@ import {
   SearchRounded,
   Groups,
   RssFeed,
-  PostAdd,
   Chat,
   ExpandLess,
   ExpandMore,

src/components/navigation/BottomNavigation.tsx

@@ -7,7 +7,6 @@ import {
 import {
   RssFeed,
   Hub,
-  PostAdd,
   Chat,
   Groups,
 } from '@mui/icons-material';

src/pages/GroupDetailPage.tsx

@@ -11,7 +11,6 @@ import {
   IconButton,
   Button,
   Chip,
-  Divider,
   Badge,
   alpha,
   useTheme
@@ -27,7 +26,6 @@ import {
   Comment,
   Share,
   MoreVert,
-  FolderShared,
   Description,
   TableChart,
   PersonAdd

src/pages/SocialContractPage.tsx

@@ -6,8 +6,6 @@ import {
   Box,
   Paper,
   Button,
-  Avatar,
-  Chip,
   Dialog,
   DialogTitle,
   DialogContent,
@@ -22,7 +20,6 @@ import {
 } from '@mui/material';
 import {
   Security,
-  Groups,
   Favorite,
   Psychology,
   AccountTree,