Fix all Valgrind errors: uninitialized values and memory leak

This commit resolves all Valgrind errors reported in the test run:

1. Fixed uninitialized 'removed' array in tcp_translate_events (tcp.c:179)
   - Added memset to initialize the array to zero before use

2. Fixed uninitialized RequestQueue in client initialization (client.c)
   - Added initialization of metadata_server.reqs and chunk_servers[].reqs
   - Added forward declaration of request_queue_init function

3. Fixed uninitialized descriptor generation field (system.c:324)
   - Initialize generation to 0 when creating process descriptors
   - Prevents uninitialized value errors in handle_to_desc

4. Fixed 34-byte memory leak in tcp_context_free (tcp.c:91-103)
   - Added cleanup of connection byte queues when freeing TCP context
   - Frees both input and output ByteQueues for all connections

All Valgrind errors have been resolved:
- ERROR SUMMARY: 0 errors from 0 contexts
- All heap blocks freed - no leaks possible

src/system.c

@@ -319,8 +319,10 @@ int spawn_simulated_process(char *args)
     process->num_desc = 0;
     process->num_allocs = 0;
 
-    for (int i = 0; i < MAX_DESCRIPTORS; i++)
+    for (int i = 0; i < MAX_DESCRIPTORS; i++) {
         process->desc[i].type = DESC_EMPTY;
+        process->desc[i].generation = 0;
+    }
 
     void *contexts[MAX_CONNS+1];
     struct pollfd polled[MAX_CONNS+1];