no connectivity over ipv6

While this is likely an issue with my modem/ISP. it should be better handled.

for now, I did this:

`sudo nano /etc/sysctl.conf`

append the following lines to turn off ipv6:
```
net.ipv6.conf.all.disable_ipv6 = 1
net.ipv6.conf.default.disable_ipv6 = 1
net.ipv6.conf.lo.disable_ipv6 = 1
```
run `sudo sysctl -p` to take effect or just reboot.

from https://raspberrypi.stackexchange.com/a/78278

Start by reproducing the IPv6 connectivity problem on BlueOS hardware and compare behavior with IPv6 disabled through /etc/sysctl.conf and sudo sysctl -p. Trace how the system currently handles network configuration, then define done as handling the failure without requiring users to manually disable IPv6.

Written by the indexing model from the issue text.