feat: add match slugs for security and fix message history loading

Security improvements:
- Add random CUID slugs to Match model to prevent ID enumeration attacks
- Update all match URLs from /matches/:id to /matches/:slug
- Keep numeric IDs for internal Socket.IO operations only

Backend changes:
- Add slug field to matches table with unique index
- Update all match endpoints to use slug-based lookups (GET, PUT, DELETE)
- Add GET /api/matches/:slug/messages endpoint to fetch message history
- Include matchSlug in all Socket.IO notifications

Frontend changes:
- Update all match routes to use slug parameter
- Update MatchesPage to use slug for accept/reject/navigate operations
- Update MatchChatPage to fetch match data by slug and load message history
- Update RatePartnerPage to use slug parameter
- Add matchesAPI.getMatchMessages() function

Bug fixes:
- Fix MatchChatPage not loading message history from database on mount
- Messages now persist and display correctly when users reconnect

backend/src/routes/matches.js

@@ -135,6 +135,7 @@ router.post('/', authenticate, async (req, res, next) => {
       const targetSocketRoom = `user_${targetUserId}`;
       io.to(targetSocketRoom).emit('match_request_received', {
         matchId: match.id,
+        matchSlug: match.slug,
         from: {
           id: match.user1.id,
           username: match.user1.username,
@@ -255,6 +256,7 @@ router.get('/', authenticate, async (req, res, next) => {
 
       return {
         id: match.id,
+        slug: match.slug,
         partner: {
           id: partner.id,
           username: partner.username,
@@ -280,14 +282,94 @@ router.get('/', authenticate, async (req, res, next) => {
   }
 });
 
-// GET /api/matches/:id - Get specific match
-router.get('/:id', authenticate, async (req, res, next) => {
+// GET /api/matches/:slug/messages - Get messages for a match
+router.get('/:slug/messages', authenticate, async (req, res, next) => {
   try {
-    const { id } = req.params;
+    const { slug } = req.params;
+    const userId = req.user.id;
+
+    // Find match
+    const match = await prisma.match.findUnique({
+      where: { slug },
+      select: {
+        id: true,
+        user1Id: true,
+        user2Id: true,
+        roomId: true,
+        status: true,
+      },
+    });
+
+    if (!match) {
+      return res.status(404).json({
+        success: false,
+        error: 'Match not found',
+      });
+    }
+
+    // Check authorization
+    if (match.user1Id !== userId && match.user2Id !== userId) {
+      return res.status(403).json({
+        success: false,
+        error: 'You are not authorized to view messages for this match',
+      });
+    }
+
+    // Check if match is accepted
+    if (match.status !== 'accepted' || !match.roomId) {
+      return res.status(400).json({
+        success: false,
+        error: 'Match must be accepted before viewing messages',
+      });
+    }
+
+    // Get messages
+    const messages = await prisma.message.findMany({
+      where: { roomId: match.roomId },
+      include: {
+        user: {
+          select: {
+            id: true,
+            username: true,
+            avatar: true,
+            firstName: true,
+            lastName: true,
+          },
+        },
+      },
+      orderBy: { createdAt: 'asc' },
+      take: 100, // Last 100 messages
+    });
+
+    res.json({
+      success: true,
+      count: messages.length,
+      data: messages.map(msg => ({
+        id: msg.id,
+        roomId: msg.roomId,
+        userId: msg.user.id,
+        username: msg.user.username,
+        avatar: msg.user.avatar,
+        firstName: msg.user.firstName,
+        lastName: msg.user.lastName,
+        content: msg.content,
+        type: msg.type,
+        createdAt: msg.createdAt,
+      })),
+    });
+  } catch (error) {
+    next(error);
+  }
+});
+
+// GET /api/matches/:slug - Get specific match
+router.get('/:slug', authenticate, async (req, res, next) => {
+  try {
+    const { slug } = req.params;
     const userId = req.user.id;
 
     const match = await prisma.match.findUnique({
-      where: { id: parseInt(id) },
+      where: { slug },
       include: {
         user1: {
           select: {
@@ -349,6 +431,7 @@ router.get('/:id', authenticate, async (req, res, next) => {
       success: true,
       data: {
         id: match.id,
+        slug: match.slug,
         partner: {
           id: partner.id,
           username: partner.username,
@@ -368,15 +451,15 @@ router.get('/:id', authenticate, async (req, res, next) => {
   }
 });
 
-// PUT /api/matches/:id/accept - Accept a pending match
-router.put('/:id/accept', authenticate, async (req, res, next) => {
+// PUT /api/matches/:slug/accept - Accept a pending match
+router.put('/:slug/accept', authenticate, async (req, res, next) => {
   try {
-    const { id } = req.params;
+    const { slug } = req.params;
     const userId = req.user.id;
 
     // Find match
     const match = await prisma.match.findUnique({
-      where: { id: parseInt(id) },
+      where: { slug },
       include: {
         user1: {
           select: {
@@ -437,7 +520,7 @@ router.put('/:id/accept', authenticate, async (req, res, next) => {
 
       // Update match status and link to chat room
       const updated = await tx.match.update({
-        where: { id: parseInt(id) },
+        where: { slug },
         data: {
           status: 'accepted',
           roomId: chatRoom.id,
@@ -487,6 +570,7 @@ router.put('/:id/accept', authenticate, async (req, res, next) => {
 
       const notification = {
         matchId: updatedMatch.id,
+        matchSlug: updatedMatch.slug,
         roomId: updatedMatch.roomId,
         event: {
           slug: updatedMatch.event.slug,
@@ -523,6 +607,7 @@ router.put('/:id/accept', authenticate, async (req, res, next) => {
       success: true,
       data: {
         id: updatedMatch.id,
+        slug: updatedMatch.slug,
         partner: {
           id: partner.id,
           username: partner.username,
@@ -542,15 +627,15 @@ router.put('/:id/accept', authenticate, async (req, res, next) => {
   }
 });
 
-// DELETE /api/matches/:id - Reject or cancel a match
-router.delete('/:id', authenticate, async (req, res, next) => {
+// DELETE /api/matches/:slug - Reject or cancel a match
+router.delete('/:slug', authenticate, async (req, res, next) => {
   try {
-    const { id } = req.params;
+    const { slug } = req.params;
     const userId = req.user.id;
 
     // Find match
     const match = await prisma.match.findUnique({
-      where: { id: parseInt(id) },
+      where: { slug },
       include: {
         event: {
           select: {
@@ -586,7 +671,7 @@ router.delete('/:id', authenticate, async (req, res, next) => {
 
     // Delete match (will cascade delete chat room if exists)
     await prisma.match.delete({
-      where: { id: parseInt(id) },
+      where: { slug },
     });
 
     // Emit socket event to the other user
@@ -597,6 +682,7 @@ router.delete('/:id', authenticate, async (req, res, next) => {
 
       io.to(otherUserSocketRoom).emit('match_cancelled', {
         matchId: match.id,
+        matchSlug: match.slug,
         event: {
           slug: match.event.slug,
           name: match.event.name,