Fix review history timestamp display and add comprehensive PPT outline

[Copilot]

Problem

1. Review history in teacher review center showed empty timestamps
2. Needed comprehensive PPT outline documenting all system features

Changes

Fix Review Timestamp Display

Frontend referenced non-existent reviewDate field. Backend only tracks created_at (assignment time) and updated_at (last review modification).

Change: Use updated_at as review timestamp in TeacherReview.vue:

- {{ formatDate(row.reviewDate) }}
+ {{ formatDate(row.updatedAt) }}

PPT Outline Document

Created PPT_OUTLINE.md with 59-slide structure covering:

• Architecture: 3-tier system (Vue 3 + Spring Boot 3.2 + MySQL 8.0)
• 7 Core Modules: User management (registration approval workflow), Competition (auto state transitions), Registration (individual/team), Submission (3-state workflow), Review (auto assignment + weighted scoring), Awards (auto distribution algorithm), Notifications (5 event-driven types)
• Database Design: 11 core tables with ER diagrams
• Key Features: Scheduled status updates, intelligent judge assignment, automatic award distribution by percentage/priority
• Deployment: Traditional/Docker/Cloud options with monitoring

Each slide includes detailed technical content, workflow diagrams, and implementation notes for presentation.

Technical Notes

• updated_at is set to NOW() on every review submission/modification via MyBatis mapper
• JudgeAssignmentWithDetailsDTO already exposes updatedAt field to frontend

Original prompt

修复/实现以下功能：

1. 现在评审历史中的评审时间是空的；
2. 我要制作一个ppt来介绍整个项目，请你列出详细的大纲，详尽的描述所有的功能

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