Projects (F4) in IMS2 — business logic for the user

Projects are the mirror opposite of Orders: here we ourselves want to
manufacture/assemble a certain quantity of products, and we track how much
has already been made, plus see in advance which components will fall
short.

1. Structure

• Project (header) — period (a start and end date), comment. Unlike
  Orders, there's no "customer" here — a project is internal.
• Line — a product (an item with a recipe/BOM, see Tools → Products),
  with fields:
• Target — how much needs to be made.
• Made — how much has already been made, accumulates as
  manufacture happens. Starts at 0.

A line can technically be added without a recipe — but then the system
can't compute which components are short (see §3), and such a line is
flagged with a warning ("⚠ N without BOM") in the list.

2. How manufacturing happens

Same as Orders — the Projects screen itself makes nothing, it's just a
list of "what's needed". Actual manufacturing happens through the Workshop
form (the "Project" button): pick an open project line, enter the
quantity made, the document is processed as manufacture (consumes
components per the recipe, receives the finished product).

When the document is processed:
- the made quantity is added to the line's made total;
- when the made total equals the target — the line closes automatically;
- when all lines are closed — the project closes automatically.

3. The "Components" tab — what's short for assembly

A separate tab inside a project computes on the fly (stores nothing)
how much of each component is needed to make everything still remaining
across all open lines:

1. Takes each product's recipe (BOM) from Products/BOM.
2. Multiplies by the line's remaining quantity (target minus already
   made).
3. Sums across all project lines — one component can be part of several
   different products at once, shown as a single row with the combined
   requirement.
4. Compares against current stock on hand — the Deficit column shows
   directly what and how much is short.

This is "what needs to be bought" reconnaissance, not a document and not a
reservation — refreshed with the Refresh button, doesn't process or
lock anything.

Example. A birthday party project: the target is 40 servings of Pizza
Margherita. Each serving's BOM: 1 unit dough, 0.2 unit tomato sauce, 0.3
unit mozzarella cheese, 0.02 unit fresh basil. With 0 made so far and
current stock of 50 dough / 10 sauce / 5 cheese / 0.3 basil, the
Components tab computes the requirement for all 40 remaining servings (40
dough, 8 sauce, 12 cheese, 0.8 basil) and shows the Deficit against stock:
dough 0 (covered by 50 on hand), sauce 0 (covered by 10), cheese 7 short
(need 12, have 5), basil 0.5 short (need 0.8, have 0.3). This tells the
buyer exactly what to order before the party, without reserving anything
or blocking the project.

4. Manual close

The Close Project button forcibly closes a project even if something
isn't finished (same as Close Order in Orders).

5. Editing restrictions

Same rules as Orders: the target can't be reduced below what's already
made, a line with an already-made quantity can't be deleted, a project
with at least one non-empty line can't be deleted.

6. Notifications

Same as Orders — closing a line/project is visible in the general log
(Tools → Events → Events), but does not pop up on the main-screen
panel (that panel only shows stock shortages).

7. Report

Project Cost Report — a separate button inside a project, cost based
on what was actually made (not on the target) — separate from the general
reports system, called directly.