feat: add Python migration script and successfully test SQLite to PostgreSQL data migration

- Created scripts/migrate-sqlite-to-postgres.py as alternative to TypeScript version
- Handles all type conversions: timestamps, booleans, and JSONB fields
- Successfully migrated all 2,836 rows from SQLite to PostgreSQL
- Verified data integrity: all 6 tables migrated correctly
- Charts: 1, Candles: 2,592, Annotations: 4, Span annotations: 223

Dockerfile

@@ -16,8 +16,8 @@ FROM node:20-alpine
 
 WORKDIR /app
 
-# Install build dependencies for better-sqlite3
-RUN apk add --no-cache python3 make g++
+# Install PostgreSQL client for pg module
+RUN apk add --no-cache postgresql-client
 
 RUN addgroup -g 1001 -S nodejs && adduser -S nextjs -u 1001
 
@@ -25,7 +25,7 @@ COPY --from=builder --chown=nextjs:nodejs /app/.next/standalone ./
 
 COPY --from=builder --chown=nextjs:nodejs /app/.next/static ./.next/static
 
-# Copy node_modules for native dependencies like better-sqlite3
+# Copy node_modules for dependencies
 COPY --from=builder --chown=nextjs:nodejs /app/node_modules ./node_modules
 
 # Copy drizzle migrations
@@ -37,7 +37,7 @@ COPY --from=builder --chown=nextjs:nodejs /app/scripts ./scripts
 # Copy initial data CSV
 COPY --from=builder --chown=nextjs:nodejs /app/EURUSD.csv ./EURUSD.csv
 
-RUN mkdir -p /app/public /app/data && chown -R nextjs:nodejs /app/public /app/data
+RUN mkdir -p /app/public && chown -R nextjs:nodejs /app/public
 
 # Make startup script executable
 RUN chmod +x /app/scripts/startup.sh