[demand] Create / document decision matrix for updating demanded inventory

[agritheory]

Currently there are three documents that can remove inventory demand: Stock Entry, Delivery Note and Sales Invoice (with 'Update Stock' checked). This code needs to be added to the demand feature branch and would be best served with a TDD approach since manually executing or evaporating stock transaction is onerous. These documents need to reconcile the demanding Sales Order or Work Order and their satisfaction. There's a subcontracting workflow that also needs to be tested but it will likely be solved with listening on Stock Entries.

The first step for this issue should to design a decision matrix, like the one we've spec'd for Handling Units. Both of these could benefit from additional clarity about the Stock Entry type, since that does change the behavior.

In prose, I think we should specify it like this:

When a Stock Entry with a purpose of "Transfer" is submitted, update demand for that Item, subject to warehouse filtering, increasing demand for target warehouse, decreasing demand in source warehouse.

When a Stock Entry with a purpose of "Transfer" is cancelled, update demand for that Item, subject to warehouse filtering, decreasing demand for target warehouse, increasing demand in source warehouse.

With this laid out, the test regime also becomes clear and we can align the desired outcome.

[Alchez]

@agritheory are you looking for something like this? Or in a different format?

Doctype	Action	Source Warehouse Demand	Target Warehouse Demand	Stock Transaction Type
Delivery Note	Submit	Increase
Delivery Note	Cancel	Decrease
Sales Invoice	Submit	Increase		Sales Fulfillment
Sales Invoice	Cancel	Decrease		Sales Fulfillment
Sales Invoice	Submit	Decrease		Sales Return
Sales Invoice	Cancel	Increase		Sales Return
Stock Entry	Submit	Decrease	Increase	Material Transfer for Manufacture
Stock Entry	Cancel	Increase	Decrease	Material Transfer for Manufacture
Stock Entry	Submit	Decrease		Material Issue
Stock Entry	Cancel	Increase		Material Issue
Stock Entry	Submit	Increase		Material Receipt
Stock Entry	Cancel	Decrease		Material Receipt
Stock Entry	Submit	Decrease	Increase	Material Transfer
Stock Entry	Cancel	Increase	Decrease	Material Transfer
Stock Entry	Submit	Decrease	Increase	Manufacture
Stock Entry	Cancel	Increase	Decrease	Manufacture
Stock Entry	Submit	Decrease	Increase	Repack
Stock Entry	Cancel	Increase	Decrease	Repack
Stock Entry	Submit	Decrease	Increase	Send to Subcontractor
Stock Entry	Cancel	Increase	Decrease	Send to Subcontractor
Purchase Invoice	Submit		Increase	Purchase Receipt
Purchase Invoice	Cancel		Decrease	Purchase Receipt
Purchase Invoice	Submit		Decrease	Purchase Return
Purchase Invoice	Cancel		Increase	Purchase Return
Purchase Receipt	Submit		Increase
Purchase Receipt	Cancel		Decrease
Stock Reconciliation	Submit		Adjustment
Stock Reconciliation	Cancel		Adjustment

[agritheory]

@Alchez That looks good. I think we can build out the function using this as the base. It should exposed in hooks the same way that other BEAM actions are.