docs: add universal moderators handbook (#39417)

* docs: add universal moderators handbook

* Update docs/flight-manuals/moderator-handbook.md

Co-authored-by: Randell Dawson <5313213+RandellDawson@users.noreply.github.com>

* Apply suggestions from code review

Co-authored-by: Randell Dawson <5313213+RandellDawson@users.noreply.github.com>
Co-authored-by: Nicholas Carrigan <nhcarrigan@gmail.com>

* Update docs/flight-manuals/moderator-handbook.md

Co-authored-by: Randell Dawson <5313213+RandellDawson@users.noreply.github.com>

* Update docs/flight-manuals/moderator-handbook.md

Co-authored-by: Nicholas Carrigan <nhcarrigan@gmail.com>

* Update docs/flight-manuals/moderator-handbook.md

Co-authored-by: Shaun Hamilton <51722130+Sky020@users.noreply.github.com>

Co-authored-by: Randell Dawson <5313213+RandellDawson@users.noreply.github.com>
Co-authored-by: Nicholas Carrigan <nhcarrigan@gmail.com>
Co-authored-by: Shaun Hamilton <51722130+Sky020@users.noreply.github.com>

docs/_sidebar.md

@@ -1,6 +1,6 @@
 - **<i class="fad fa-hourglass-start"></i> Getting Started**
   - [Introduction](/index.md 'Contribute to the freeCodeCamp.org Community')
-- **<i class="fad fa-code"></i> Code Contribution Guides**
+- **<i class="fad fa-code"></i> Code Contribution**
   - [Work on coding challenges](/how-to-work-on-coding-challenges.md)
   - [Help with video challenges](/how-to-help-with-video-challenges.md)
   - [Set up freeCodeCamp locally](/how-to-setup-freecodecamp-locally.md)
@@ -9,14 +9,21 @@
   - [Work on the docs theme](/how-to-work-on-the-docs-theme.md)
   - [Catch outgoing emails locally](/how-to-catch-outgoing-emails-locally.md)
   - [Set up WSL](/how-to-setup-wsl.md)
-- **<i class="fad fa-language"></i> Chinese Community Contribution Guides** (中文社区贡献指南)
+
+---
+
+- **<i class="fad fa-plane-alt"></i> Flight Manuals** (for Staff & Mods)
+  - [Moderator Handbook](/flight-manuals/moderator-handbook.md)
+  - [Reply Templates](/flight-manuals/using-reply-templates.md)
+  - [DevOps Overview](/devops.md)
+  - [Working on Servers](/flight-manuals/working-on-virtual-machines.md)
+
+---
+
+- **<i class="fad fa-language"></i> 中文社区贡献指南**
   - [成为专栏作者](/chinese-guides/news-author-application.md)
   - [文章翻译计划](/chinese-guides/news-translations.md)
   - [视频翻译计划](/chinese-guides/video-translations.md)
-- **<i class="fad fa-plane-alt"></i> Flight Manuals** (for Staff & Mods)
-  - [DevOps Overview](/devops.md)
-  - [Reply Templates](/flight-manuals/using-reply-templates.md)
-  - [Working on Servers](/flight-manuals/working-on-virtual-machines.md)
 
 ---