[24_13] Pandoc-binary doc (XmacsLabs#1972)

<!-- Thank you for your contribution! -->
## What
Add Pandoc binary document and move pandoc.scm to right place.
## Why

## How to test your changes?

TeXmacs/plugins/pandoc/progs/binary/pandoc-binary.scm → TeXmacs/plugins/binary/progs/binary/pandoc.scm

@@ -1,6 +1,6 @@
 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
 ;;
-;; MODULE      : pandoc-binary.scm
+;; MODULE      : pandoc.scm
 ;; DESCRIPTION : Pandoc Binary plugin
 ;; COPYRIGHT   : (C) 2024  ATQlove
 ;;

docs/guide/plugin_binary_pandoc.md

@@ -0,0 +1,28 @@
+# Pandoc Binary Plugin
++ Executable filename: `pandoc`
++ Plugin source code:
+  - [Codeberg](https://codeberg.org/XmacsLabs/mogan/src/branch/branch-1.2/TeXmacs/plugins/binary/progs/binary/pandoc.scm)
+  - [Gitee](https://gitee.com/XmacsLabs/mogan/blob/branch-1.2/TeXmacs/plugins/binary/progs/binary/pandoc.scm)
+  - [Github](https://github.com/XmacsLabs/mogan/blob/branch-1.2/TeXmacs/plugins/binary/progs/binary/pandoc.scm)
+- What: Supports the `Document Conversion -> Export to Multiple Formats` feature
+- Mogan: `>= v1.2.8`
+
+## How to Install Pandoc
+### Windows
+Install using `Chocolatey`:
+```
+choco install pandoc
+```
+Install using `winget`:
+```
+winget install --source winget --exact --id JohnMacFarlane.Pandoc
+```
+
+### macOS
+Install using `brew install pandoc`.
+
+### Linux
+On Debian bookworm, use the following command to install:
+```
+sudo apt install pandoc
+```

docs/zh/guide/plugin_binary_pandoc.md

@@ -0,0 +1,28 @@
+# Pandoc 二进制插件
++ 可执行文件名：pandoc
++ 插件源代码：
+  - [Codeberg](https://codeberg.org/XmacsLabs/mogan/src/branch/branch-1.2/TeXmacs/plugins/binary/progs/binary/pandoc.scm)
+  - [Gitee](https://gitee.com/XmacsLabs/mogan/blob/branch-1.2/TeXmacs/plugins/binary/progs/binary/pandoc.scm)
+  - [Github](https://github.com/XmacsLabs/mogan/blob/branch-1.2/TeXmacs/plugins/binary/progs/binary/pandoc.scm)
+- 功能：支持`文档转换->导出到多种格式`
++ 墨干：`>= v1.2.8`
+
+## 如何安装 Pandoc
+### Windows
+使用`Chocolatey`安装：
+```
+choco install pandoc
+```
+使用`winget`安装：
+```
+winget install --source winget --exact --id JohnMacFarlane.Pandoc
+```
+
+### macOS
+使用`brew install pandoc`安装。
+
+### Linux
+在Debian bookworm中，使用如下命令安装：
+```
+sudo apt install pandoc
+```