Feature/curriculum feedback and performance trends

[DikshyaSoni]

🚀 New Features Added

1. Curriculum Feedback (CurriculumFeedback.tsx)

   • Automatically flags competencies where $\ge 40%$ of students perform poorly.
   • Categorizes weak topics by severity (Critical, Needs Attention, Monitor).
   • Provides specific curriculum recommendations and lists affected students for Admin & Superadmin roles.

2. Performance Trend Indicator (PerformanceTrendIndicator.tsx)

   • Analyzes student level history to categorize trajectories into Improving 📈, Stable ➡️, and Declining 📉.
   • Adds a compact view in the Performance panel and a standalone filterable Trends dashboard for Teachers & School admins.

📁 Files Modified / Added

• New Components: CurriculumFeedback.tsx, PerformanceTrendIndicator.tsx
• Updated Files: Layout.tsx (navigation), PanelViews.tsx (routing), index.css (animations), FEATURE_CHANGES.md (docs)