Normalize composite tunnel display values before rendering peer and
debug output so IPv6 tunnel types no longer append `6` to the port.
- Preserve prefixes like `txt-` while converting tunnel schemes to
their IPv6 form.
- Recover malformed values such as `txt-tcp://...:110106` into
`txt-tcp6://...:11010`.
- Reuse the normalized remote address display in CLI debug output.
1. avoid dns query hangs the thread
2. avoid deadloop when stun query failed because of no ipv4 addr.
3. make quic input error non-fatal.
4. remove ring tunnel from connection map to avoid mem leak.
5. limit listener retry count.
1. dns resolver should be global unique so dns cache can work. avoid dns query influence hole punching.
2. when system dns failed, fallback to hickory dns.
* fix peer rpc stop working because of mpsc tunnel close unexpectedly
* fix gui:
1. allow set network prefix for virtual ipv4
2. fix android crash
3. fix subnet proxy cannot be set on android
This patch removes Tarpc & Tonic GRPC and implements a customized rpc framework, which can be used by peer rpc and cli interface.
web config server can also use this rpc framework.
moreover, rewrite the public server logic, use ospf route to implement public server based networking. this make public server mesh possible.