Android: network-range posture checks never match because the client reports empty NetworkAddresses

[MichaelUray]

What I'm trying to do
Use a peer_network_range_check posture check so that a device physically inside a trusted subnet (e.g. a phone on the home Wi-Fi) is treated differently from one on a foreign network — e.g. not pushing an overlay route that overlaps that local subnet.

What I observe
On Linux and Windows this works: the client reports its local subnet in NetworkAddresses, and the range check matches. On Android, the same setup never matches — the peer reports an empty NetworkAddresses to management, so the check is effectively a no-op on Android.

Root cause (as far as I can tell)
client/system/info_android.go doesn't populate NetworkAddresses the way the other platforms do via networkAddresses(). On top of that, net.Interfaces() under Android's VpnService sandbox doesn't reliably expose the Wi-Fi IPv4 anyway, so even calling it wouldn't be enough.

What I'd like your take on, before I open any PRs

1. Reporting: would you be open to populating NetworkAddresses on Android by reusing the existing IFaceDiscover bridge (it already enumerates the local interfaces for ICE candidate gathering and does see the LAN addresses), rather than net.Interfaces()?
2. Re-evaluation on network change: today a Wi-Fi↔cellular switch is handled by restarting the engine. For posture, a lighter option would be a dedicated "underlying network changed" re-sync that just re-reports NetworkAddresses without a full restart. Do you have a preference between the two, or a direction you'd want this to take?

I have a working prototype of both on a fork (device-verified on a real Android phone) and I'm happy to turn it into proper PRs — netbird core first, then android-client — if there's interest and agreement on the approach. I had a first, android-only attempt in netbirdio/android-client#154 (now closed) — it only covered the trigger and relied on core changes that aren't upstream, which is exactly why I'd rather align on the full approach here before opening PRs. Thanks!