CSV Import: Preview endpoint (no database writes)

[azunaVT]

Epic: Import

Description

Add an endpoint to upload a CSV file and preview normalized transactions without persisting anything to the database.

Endpoint

• POST /api/v1/imports/csv/preview

Acceptance Criteria

• Accepts a CSV file upload
• Parses rows into a normalized structure:
  • occurred_on (date)
  • description (string)
  • amount_cents (integer)
  • currency (default CAD)
• Supports basic column mapping (minimal is fine)
• Does not write anything to the database
• Returns parsed rows as JSON
• Request spec included