"Import Bank Statement" button and customizable bank statement formats

[salieg72]

Is your feature request related to a problem? Please describe.
Currently, users must manually configure or customize the bank statement import process to match their specific bank's format. This process is technical and not user-friendly, particularly when working with multiple banks or changing formats. There is also no clear way to manage multiple statement formats within the system.

Describe the solution you'd like
Add an "Import Bank Statement" button directly in the Bank Statement Import doctype that:

• Opens a file upload dialog and detects the format based on a selected or predefined Bank Statement Format doctype.
• Allows users to create and manage multiple bank statement format definitions via a new Bank Statement Format doctype.
• Supports defining field mappings, delimiters, headers, and required fields per bank format.
• Enables selecting or assigning a format per import for flexible use.

This approach would make it easier to manage varying statement formats and enable non-developers to add or adjust import templates without custom coding.

Describe alternatives you've considered
Editing the codebase or scripts for each new bank format, which is not scalable or user-friendly.

Using third-party tools to standardize the statement before import.

Additional context
Many ERP systems provide a flexible way to import bank statements from different banks, allowing users to map columns and formats via a UI. Introducing a dedicated Bank Statement Format doctype would empower users to adapt ERPNext to their financial institutions with minimal effort, and streamline reconciliation workflows.