Collect ip route change

Add metrics for ip route change( add / del) count.
Better print detail change (dst ip and gateway) to log.

Here is bpftrace example:
```
bpftrace -e 'kprobe:fib_table_insert {printf("%s/%d via %s \n", ntop(((struct fib_config *)arg2)->fc_dst), ((struct fib_config *)arg2)->fc_dst_len, ntop(((struct fib_config *)arg2)->fc_gw4) )}'

bpftrace -e 'kprobe:fib_table_delete {printf("%s/%d \n", ntop(((struct fib_config *)arg2)->fc_dst), ((struct fib_config *)arg2)->fc_dst_len )}'

```

Start by examining the existing network monitoring paths and the fib_table_insert and fib_table_delete kprobes shown in the issue's bpftrace examples. Determine where route metrics and logs are collected; done means recording add/delete counts and logging the destination IP and gateway for route changes.

Written by the indexing model from the issue text.