Sync fairmint/OCP Changes

[AdamMomen]

Summary

This update refactors the database schema and API to be more efficient and removes the redundant HistoricalTransaction collection. It also streamlines the migration script for better automation. For more info check #95.

Changes

• Removed HistoricalTransaction Collection: Eliminated the centralized HistoricalTransaction model and its associated database operations.
• Added tx_hash to Transaction Objects: All transaction documents (e.g., StockIssuance, StockCancellation) now store the on-chain transaction hash directly.
• New StockCancellation Model: Introduced a new model and database operations for handling stock cancellations.
• Streamlined Migration Script: Removed interactive environment confirmations to make the migrate.js script more automatable and introduced an ISSUERS_TO_MIGRATE list for targeted migrations.
• API Updates: Endpoints that create on-chain transactions now return the tx_hash in the response body.
• Code Cleanup:
  • Refactored the Factory schema for clarity.
  • Corrected a typo from removeAllListeners to reamoveAllListeners.