[FIX] stock: replenish report in 3 months

Currently the replenishment report look for forecasted quantity of
product today. It means that for a product if the delivery is planned
for today the forecast will be -1, at j-1 it will be 0. However for the
majority of use case, products take days to order and arrive.

Example:
- Product A, purchase delivery time 5 days.
- You are the 01-01-2021 and create a SO for 10-01-2021
Currently:
- Product will appear in the replenishment report the 10-01-2021 and
you will receive it the 15-01-2021. So you are late to deliver your
customer.
Desired behavior:
- Product appear in the replenishment report the 05-01-2021 and if you
order it directly you will receive it the 10-01-2021.

If you want to have more time to deliver than one day, security lead
time are there for it.

However the usecase like:
Product arrive in 2 months and you receive it in 3 days, the product won't
appear in the replenish report anymore since the forecast in 3months is
0

It could happens that more product are missing in 3 months than today,
so the system could have more delivery lead times and forecast at date
to compute -> be slower. In that case a parameter could be
added to skip the delivery times computation for each product/warehouse
and just display the forecast in 3 months and let user compute their
schedule themself.

closes odoo/odoo#73737

X-original-commit: f988b7629f8f54e8e3f48bf76e6af9d97b4f47da
Signed-off-by: Arnold Moyaux <amoyaux@users.noreply.github.com>

addons/stock/models/stock_orderpoint.py

@@ -12,7 +12,7 @@ from odoo import SUPERUSER_ID, _, api, fields, models, registry
 from odoo.addons.stock.models.stock_rule import ProcurementException
 from odoo.exceptions import UserError, ValidationError
 from odoo.osv import expression
-from odoo.tools import float_compare, frozendict, split_every
+from odoo.tools import add, float_compare, frozendict, split_every
 
 _logger = logging.getLogger(__name__)
 
@@ -313,8 +313,10 @@ class StockWarehouseOrderpoint(models.Model):
         to_refill = defaultdict(float)
         all_product_ids = []
         all_warehouse_ids = []
+        # Take 3 months since it's the max for the forecast report
+        to_date = add(fields.date.today(), months=3)
         qty_by_product_warehouse = self.env['report.stock.quantity'].read_group(
-            [('date', '=', fields.date.today()), ('state', '=', 'forecast')],
+            [('date', '=', to_date), ('state', '=', 'forecast')],
             ['product_id', 'product_qty', 'warehouse_id'],
             ['product_id', 'warehouse_id'], lazy=False)
         for group in qty_by_product_warehouse: