Add Support for Interest Engine to Manage and Apply Interest Rates to Balances

[jerry-enebeli]

Is your feature request related to a problem? Please describe.

Blnk does not currently have a way to work with interest rates and apply them to balances. This makes it challenging to automate processes like accruing interest for credit or debit balances.

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Describe the solution you'd like

would like Blnk to include an Interest Engine as part of its ledger. This engine should:

• Allow developers to define and manage interest rules dynamically, such as interest rate, compounding frequency, and applicable balance types.
• Support both credit and debit interest.
• Handle simple and compound interest calculations.
• Automate the application of interest at customizable intervals (e.g., daily, monthly).
• Post interest calculations to the db ensuring traceability.

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Describe alternatives you've considered

1. Manual Interest Handling: Manually calculating and applying interest, which is inefficient and error-prone.
2. Custom Scripts: Writing scripts to handle interest logic, but this is time-intensive and not scalable.
3. External Systems: Relying on third-party tools for interest calculations, which reduces flexibility and increases complexity.

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Additional context

This feature would enable users to automate interest application workflows. For example, a business could define a rule like 5% annual compound interest, compounded monthly, on balances exceeding $1,000, and the engine would handle the calculations and updates automatically.