frp, frpc, frps: add page (#12945)

Co-authored-by: spageektti <git@spageektti.cc>
Co-authored-by: K.B.Dharun Krishna <kbdharunkrishna@gmail.com>
Co-authored-by: Sebastiaan Speck <12570668+sebastiaanspeck@users.noreply.github.com>
Co-authored-by: Vítor Henrique <87824454+vitorhcl@users.noreply.github.com>

pages/common/frps.md

@@ -0,0 +1,29 @@
+# frps
+
+> Quickly set up a reverse proxy service.
+> Part of `frp`.
+> More information: <https://github.com/fatedier/frp>.
+
+- Start the service, using the default configuration file (assumed to be `frps.ini` in the current directory):
+
+`frps`
+
+- Start the service, using the newer TOML configuration file (`frps.toml` instead of `frps.ini`) in the current directory:
+
+`frps {{-c|--config}} ./frps.toml`
+
+- Start the service, using a specified config file:
+
+`frps {{-c|--config}} {{path/to/file}}`
+
+- Check if the configuration file is valid:
+
+`frps verify {{-c|--config}} {{path/to/file}}`
+
+- Print autocompletion setup script for Bash, Fish, PowerShell, or Zsh:
+
+`frps completion {{bash|fish|powershell|zsh}}`
+
+- Display version:
+
+`frps {{-v|--version}}`