feat: update CMS service handlers and main application logic.

services/lms-service/migrations/20231221000001_grading_system.sql

@@ -0,0 +1,25 @@
+-- Add grading categories table
+CREATE TABLE grading_categories (
+    id UUID PRIMARY KEY DEFAULT gen_random_uuid(),
+    course_id UUID NOT NULL REFERENCES courses(id) ON DELETE CASCADE,
+    name TEXT NOT NULL,
+    weight INTEGER NOT NULL CHECK (weight >= 0 AND weight <= 100),
+    drop_count INTEGER NOT NULL DEFAULT 0,
+    created_at TIMESTAMPTZ NOT NULL DEFAULT CURRENT_TIMESTAMP
+);
+
+-- Update lessons with grading fields
+ALTER TABLE lessons ADD COLUMN grading_category_id UUID REFERENCES grading_categories(id) ON DELETE SET NULL;
+ALTER TABLE lessons ADD COLUMN is_graded BOOLEAN NOT NULL DEFAULT FALSE;
+
+-- Create table to track individual student scores
+CREATE TABLE user_grades (
+    id UUID PRIMARY KEY DEFAULT gen_random_uuid(),
+    user_id UUID NOT NULL REFERENCES users(id) ON DELETE CASCADE,
+    course_id UUID NOT NULL REFERENCES courses(id) ON DELETE CASCADE,
+    lesson_id UUID NOT NULL REFERENCES lessons(id) ON DELETE CASCADE,
+    score FLOAT4 NOT NULL, -- 0.0 to 1.0 (percentage)
+    metadata JSONB, -- store specific answers or feedback
+    created_at TIMESTAMPTZ NOT NULL DEFAULT CURRENT_TIMESTAMP,
+    UNIQUE(user_id, lesson_id)
+);