feat: Add comprehensive documentation suite and reorganize project structure

- Created complete documentation in docs/ directory
- Added PROJECT_OVERVIEW.md with feature highlights and getting started guide
- Added ARCHITECTURE.md with system design and technical details
- Added SECURITY.md with comprehensive security implementation guide
- Added DEVELOPMENT.md with development workflows and best practices
- Added DEPLOYMENT.md with production deployment instructions
- Added API.md with complete REST API documentation
- Added CONTRIBUTING.md with contribution guidelines
- Added CHANGELOG.md with version history and migration notes
- Reorganized all documentation files into docs/ directory for better organization
- Updated README.md with proper documentation links and quick navigation
- Enhanced project structure with professional documentation standards

f_templates/tpl_backend/tpl_uploadjs_min.tpl

@@ -0,0 +1,4 @@
+	<script type="text/javascript">var upload_lang = new Array();upload_lang["h1"] = '{lang_entry key="upload.text.h1.select"}';upload_lang["h2"] = '{lang_entry key="upload.text.h2.select"}';upload_lang["category"] = '{lang_entry key="upload.text.categ"}';upload_lang["username"] = '{lang_entry key="upload.text.user"}';upload_lang["assign"] = '{lang_entry key="upload.text.assign.tip"}';upload_lang["tip"] = '{lang_entry key="upload.text.categ.tip"}';upload_lang["utip"] = '{lang_entry key="upload.text.user.tip"}';upload_lang["filename"] = '{lang_entry key="upload.text.filename"}';upload_lang["size"] = '{lang_entry key="upload.text.size"}';upload_lang["status"] = '{lang_entry key="upload.text.status"}';upload_lang["drag"] = '{lang_entry key="upload.text.drag"}';upload_lang["select"] = '{lang_entry key="upload.text.select"}';upload_lang["start"] = '{lang_entry key="upload.text.btn.start"}';</script>
+	<script type="text/javascript" src="{$javascript_url}/uploader/plupload.full.min.js"></script>
+	<script type="text/javascript" src="{$javascript_url}/uploader/jquery.plupload.queue/jquery.plupload.queue.min.js"></script>
+	{include file="tpl_backend/tpl_uploadjs.tpl"}