Initial commit: PastPaper Master full stack

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

supabase/migrations/002_course_library_fields.sql

@@ -0,0 +1,38 @@
+-- ============================================
+-- PastPaper Master — Shared course library fields
+-- Version: 002
+-- Date: 2026-03-24
+-- ============================================
+
+-- Shared library / canonical import metadata on papers
+ALTER TABLE papers
+  ADD COLUMN IF NOT EXISTS source_kind TEXT NOT NULL DEFAULT 'user_upload'
+    CHECK (source_kind IN ('user_upload', 'course_library')),
+  ADD COLUMN IF NOT EXISTS source_exam_key TEXT,
+  ADD COLUMN IF NOT EXISTS part_label TEXT
+    CHECK (part_label IN ('A', 'B')),
+  ADD COLUMN IF NOT EXISTS source_question_filename TEXT,
+  ADD COLUMN IF NOT EXISTS source_answer_filename TEXT;
+
+CREATE UNIQUE INDEX IF NOT EXISTS idx_papers_course_library_exam_key
+  ON papers(source_exam_key)
+  WHERE source_kind = 'course_library' AND source_exam_key IS NOT NULL;
+
+CREATE INDEX IF NOT EXISTS idx_papers_course_lookup
+  ON papers(course_code, year, term, exam_type, part_label);
+
+-- Grading results should persist awarded score
+ALTER TABLE user_attempts
+  ADD COLUMN IF NOT EXISTS score_given INTEGER;
+
+CREATE INDEX IF NOT EXISTS idx_attempts_errorbook_active
+  ON user_attempts(user_id, created_at DESC)
+  WHERE in_error_book = true AND mastered = false;
+
+-- The backend and frontend already support true_false; schema must match.
+ALTER TABLE paper_questions
+  DROP CONSTRAINT IF EXISTS paper_questions_question_type_check;
+
+ALTER TABLE paper_questions
+  ADD CONSTRAINT paper_questions_question_type_check
+  CHECK (question_type IN ('mc', 'true_false', 'fill_blank', 'long_question'));