Account Dashboard Banner MIS Builder

This module adds a new cell type called "MIS Builder KPI" to the accounting dashboard banner. When configuring a banner cell, you can now choose this type and pick a MIS Report, a KPI from that report, and a period. The cell then displays the computed value of that KPI for the selected period.

• The cell configuration form shows fields for MIS Report, MIS Report KPI, and MIS Report Period, which become required when the cell type is "MIS Builder KPI".
• For numeric KPIs, you can choose whether to display the currency symbol next to the value.
• The system checks that the selected KPI belongs to the same report template as the chosen MIS Report, and that the period belongs to the chosen MIS Report. If not, it raises a validation error.
• The KPI value is computed using the report's evaluation logic and formatted according to the KPI's style.
• If you don't set a custom label, the cell uses the KPI description as its label.
• If you don't set a custom tooltip, the cell shows a tooltip with the KPI name, the date range, and the KPI expression (when the KPI is not multi).

The module extends the account.dashboard.banner.cell model and adds fields such as mis_report_instance_id, mis_report_kpi_id, and mis_report_instance_period_id. It also modifies the banner cell form and list views to include these fields.