feat/kcp (#580)

* support proxy tcp stream with kcp to improve experience of tcp over udp
* update rust version
* make subnet proxy route metrics lower in windows.

.github/workflows/core.yml

@@ -114,6 +114,9 @@ jobs:
         if: ${{ ! endsWith(matrix.TARGET, 'freebsd') }}
         run: |
           bash ./.github/workflows/install_rust.sh
+          # this dir is a soft link generated by install_rust.sh
+          # kcp-sys need this to gen ffi bindings. without this clang may fail to find some libc headers such as bits/libc-header-start.h
+          export KCP_SYS_EXTRA_HEADER_PATH=/usr/include/musl-cross
           if [[ $OS =~ ^ubuntu.*$ && $TARGET =~ ^mips.*$ ]]; then
             cargo +nightly build -r --verbose --target $TARGET -Z build-std=std,panic_abort --no-default-features --features mips --package=easytier
           else
@@ -142,14 +145,14 @@ jobs:
             whoami
             env | sort
 
-            sudo pkg install -y git protobuf
+            sudo pkg install -y git protobuf llvm-devel
             curl --proto 'https' --tlsv1.2 -sSf https://sh.rustup.rs | sh -s -- -y
             source $HOME/.cargo/env
 
             rustup set auto-self-update disable
 
-            rustup install 1.77
-            rustup default 1.77
+            rustup install 1.84
+            rustup default 1.84
 
             export CC=clang
             export CXX=clang++