Enforce the number of trips spread

Feature Request: Trip Total Validation During Monthly Edits

Summary:
Introduce a validation option when editing monthly trips that either warns users or prevents them from saving changes if the total number of trips no longer matches the original planned amount. This ensures that month-by-month adjustments do not unintentionally alter the overall trip total.

Problem Statement:
When editing trips on a monthly basis, users can currently add or remove more trips than the original spread amount. This makes it easy to accidentally change the overall number of planned trips without realizing it. Over time, these discrepancies can lead to misaligned plans, inaccurate reporting, and confusion between what was originally approved and what is being executed.

Proposed Solution:
Add a validation check that compares the sum of monthly trips against the original total number of trips.
Provide configuration options at the appropriate admin or user level to:

• Only warn users when the total changes, but still allow them to proceed, or

• Strictly prevent saving changes if the total number of trips no longer matches the original total.
  Display a clear, actionable message indicating the original total, the new total, and the difference whenever a discrepancy is detected.
  Optionally allow authorized users to update the original total explicitly (with audit tracking) when business needs require a permanent change.

Benefits:
Reduces accidental changes to the overall number of trips during routine monthly adjustments.
Improves data accuracy and consistency between planned and actual trip counts.
Provides better control and governance over changes, especially in audited or regulated environments.
Enhances user confidence by making discrepancies visible and easy to correct.
Supports clearer alignment between approved plans and ongoing operational updates.