Feature Request: Calculated Columns in Material View

Summary:
Enable users to add custom calculated columns directly in the material view grid. Calculations should reference existing fields, apply common functions (e.g., sum, average, min/max), and display results in real time without requiring an export to Excel.

Problem Statement:
Today, users must export the material view to spreadsheets to compute totals and other derived values. This creates extra steps, introduces version control risk, and breaks workflow continuity. Results quickly become stale, forcing repeated exports and manual reconciliation.

Proposed Solution:
Allow users to create one or more calculated columns within the material view with the following capabilities:
- Formula builder that references existing columns by name and supports basic arithmetic (+, −, ×, ÷), parentheses, and functions (SUM, AVG, MIN, MAX, COUNT, IF).
- Per-row calculations (e.g., Quantity × Unit cost) and optional group-level aggregations that respect current filters and grouping.
- Type-aware outputs (number, currency, percent, duration) with configurable formatting and decimal precision.
- Inline preview and validation with clear error messages for invalid references or circular logic.
- Non-destructive: calculated columns do not overwrite source data and can be shown/hidden, reordered, duplicated, or deleted.
- Persistence: formulas are saved with the view and respected in exports and shared links.
- Performance safeguards for large datasets (e.g., lazy evaluation, limits on complex nested formulas) to ensure responsive grid interactions.
- Permissions align with view sharing: editors can create/edit formulas; viewers can see results but not modify definitions.

Benefits:
- Eliminates time-consuming Excel exports for common calculations.
- Improves data accuracy by keeping computations in the system of record.
- Speeds decision-making with real-time results that reflect current filters and groupings.
- Enhances flexibility with reusable, formatted calculated fields tailored to different workflows.
- Reduces manual errors and rework from copy/paste and repeated reconciliations.