Add comprehensive thesis management system with database migration

This commit introduces a complete thesis management interface and migrates
the system from YAML-based storage to SQLite:

Core Changes:
- Add Database.php helper class with PDO connection and entity management
- Add list.php for viewing all theses with filtering and sorting
- Add edit.php for modifying existing thesis records
- Add import.php for migrating legacy YAML data to SQLite
- Add justfile with development tasks (serve, init-test-db, etc.)

Documentation:
- Add MIGRATION.md with complete migration guide and architecture docs
- Update README.md with database setup and Just recipe instructions
- Update .gitignore to exclude test databases and error logs

Modified Forms:
- Enhanced formulaire.php with transaction-based SQLite processing
- Updated index.php with database-driven form options
- Improved thanks.php to read from database views

The new architecture provides:
- Normalized database schema (19 tables, 2 views)
- Transaction safety and referential integrity
- CRUD operations for thesis management
- Filtering by year, orientation, AP program, publication status
- Secure file handling with metadata tracking

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <noreply@anthropic.com>

formulaire/justfile

@@ -0,0 +1,78 @@
+# Justfile for Post-ERG thesis form testing
+
+# Default recipe - show available commands
+default:
+    @just --list
+
+# Create test database from schema
+init-test-db:
+    @echo "Creating test database from schema..."
+    @sqlite3 test.db < ../db/schema.sql
+    @echo "✓ Test database created: test.db"
+    @sqlite3 test.db "SELECT COUNT(*) || ' tables created' FROM sqlite_master WHERE type='table';"
+    @sqlite3 test.db "SELECT COUNT(*) || ' orientations loaded' FROM orientations;"
+    @sqlite3 test.db "SELECT COUNT(*) || ' AP programs loaded' FROM ap_programs;"
+
+# Start PHP development server
+serve: init-test-db
+    @echo "Starting PHP development server on http://localhost:3000"
+    @echo "Press Ctrl+C to stop"
+    @php -S 127.0.0.1:3000
+
+# Start server without reinitializing database
+serve-only:
+    @echo "Starting PHP development server on http://localhost:3000"
+    @echo "Press Ctrl+C to stop"
+    @php -S 127.0.0.1:3000
+
+# Clean up test database and uploaded files
+cleanup:
+    @echo "Cleaning up test files..."
+    @rm -f test.db
+    @rm -f error.log
+    @rm -rf data/theses/*
+    @rm -rf data/covers/*
+    @echo "✓ Cleanup complete"
+
+# Reset: cleanup and reinitialize
+reset: cleanup init-test-db
+    @echo "✓ Test environment reset"
+
+# Show database statistics
+stats:
+    @echo "=== Database Statistics ==="
+    @sqlite3 test.db "SELECT COUNT(*) || ' theses' FROM theses;"
+    @sqlite3 test.db "SELECT COUNT(*) || ' authors' FROM authors;"
+    @sqlite3 test.db "SELECT COUNT(*) || ' supervisors' FROM supervisors;"
+    @sqlite3 test.db "SELECT COUNT(*) || ' keywords' FROM keywords;"
+    @sqlite3 test.db "SELECT COUNT(*) || ' files uploaded' FROM thesis_files;"
+
+# Show recent submissions
+recent:
+    @echo "=== Recent Submissions ==="
+    @sqlite3 -column -header test.db "SELECT identifier, title, year, submitted_at FROM theses ORDER BY submitted_at DESC LIMIT 5;"
+
+# Query database interactively
+query:
+    @sqlite3 test.db
+
+# Show full thesis details
+show id:
+    @sqlite3 -column -header test.db "SELECT * FROM v_theses_full WHERE id = {{id}};"
+
+# Dump database to SQL
+dump:
+    @sqlite3 test.db .dump > test_backup_$(date +%Y%m%d_%H%M%S).sql
+    @echo "✓ Database dumped to test_backup_$(date +%Y%m%d_%H%M%S).sql"
+
+# Create data directories if they don't exist
+setup-dirs:
+    @mkdir -p data/theses
+    @mkdir -p data/covers
+    @mkdir -p data/yaml
+    @touch data/theses/.gitkeep
+    @touch data/covers/.gitkeep
+    @echo "✓ Data directories created"
+
+# Full setup: directories + database + serve
+dev: setup-dirs init-test-db serve