add docs for running on Linux

README_linux.md

@@ -0,0 +1,60 @@
+# MikuSB on Linux
+
+
+## Config
+
+### setup steam launch options as following
+
+`HTTP_PROXY="http://127.0.0.1:8888" HTTPS_PROXY="http://127.0.0.1:8888" ALL_PROXY="http://127.0.0.1:8888" %command%`
+
+### start local server and keep it running
+
+```
+./MikuSB
+```
+
+### find root CA cert, and create ca bundle
+
+root CA cert, should in the path: `proxy-certs/MikuSB.Proxy.Root.pem`
+
+
+### setup root CA for proton/wine
+
+not sure, even I remove Proton PFX (Wine prefix) folder, without redo this step, still no cert issue.
+
+`Proton Hotfix` is the proton version which selected in steam `Force the use of a specific Steam Play compatibility tool`
+
+```bash
+APPID=<THE-APP-ID-OF-THE-GAME>
+STEAM_COMPAT_DATA_PATH=~/.steam/steam/steamapps/compatdata/$APPID/pfx
+STEAM_WINE_PATH="$HOME/.steam/steam/steamapps/common/Proton Hotfix/files/bin/wine"
+WINEPREFIX=$STEAM_COMPAT_DATA_PATH $STEAM_WINE_PATH certutil -addstore -f Root proxy-certs/MikuSB.Proxy.Root.pem
+```
+
+### start the game and enjoy
+
+
+## development
+
+1. Restore dependencies and build.
+
+```bash
+dotnet build
+```
+
+2. run it
+
+```bash
+dotnet run --project ./MikuSB
+```
+
+## release build
+
+```bash
+LANG=C time dotnet build -c Release
+```
+
+## TODO:
+
+* [ ] tool/script for CA cert create and install to proton/wine
+* [ ] automatic done in main program