Issue:
When the "Lock Confirmed Sales" setting is enabled, adding a product to a Field Service task would lock the associated sales order before its picking could be created. The confirmation process locks the order first , and the subsequent step to create stock moves (`_action_launch_stock_rule`) explicitly skips locked orders.

Reproducible on 17.0~master
[Task](https://www.odoo.com/odoo/action-4043/4633977)
Odoo 17:
https://drive.google.com/file/d/1qmAYhSu6gU91efuJEDF-Irn2cLGUQP0A/view?usp=drivesdk

Odoo 18:
https://drive.google.com/file/d/1x8IeXwT7ZFM7Av9Vp6GSvGIbOaEGfmVx/view?usp=drivesdk


Steps to reproduce:
1. In Sales > Configuration > Settings, enable "Lock Confirmed Sales".
2. Go to a Field Service task.
3. In the kanban view via the "Products" smart button, add a product.
4. Come back to the task, refresh the browser, open the linked Sales Order from the smart button.
5. **Before this fix:** The SO is locked, no picking is created, and SO lines will have delivered_qty set even though we haven't delivered anything.
6. **After this fix:** The SO is not locked, and a Delivery smart button is correctly displayed, linking to the generated picking.

This behavior left the sales order in an inconsistent state: it was locked, but had no corresponding delivery order. As a result, users were blocked from removing or modifying the products added to the task, as the system prevented edits on a locked order with no picking to cancel.

Let's step through what's going on here;

0. We enable "Lock Confirmed Sales" option.
1. Add a product to the Field Service(FS) task https://github.com/odoo/enterprise/blob/4256ea170c31209b83ff808e51145757571f8556/industry_fsm_sale/controllers/catalog.py#L19-L42
https://github.com/odoo/enterprise/blob/4256ea170c31209b83ff808e51145757571f8556/industry_fsm_sale/controllers/catalog.py#L38
2. set_fsm_quantity() is invoked, which will create a SO for the FS task https://github.com/odoo/enterprise/blob/35e1f47160d5840e8701fc0ad43ec42bbfaf9e36/industry_fsm_sale/models/product_product.py#L144
3. `_fsm_create_sale_order()` will immediately `action_confirm()` the new SO, because of the reasons in the function description. 
( Since we are immediately confirming newly created SO, I think we should consider not applying the "Lock Confirmed Orders" option to FSM SOs.)
https://github.com/odoo/enterprise/blob/2347dac2568dbcf83578f044f8fe41ab70a20f47/industry_fsm_stock/models/project_task.py#L124-L134 https://github.com/odoo/enterprise/blob/2347dac2568dbcf83578f044f8fe41ab70a20f47/industry_fsm_stock/models/project_task.py#L134
4. `odoo/addons/sale/models/sale_order.py/action_confirm()` will lock SO because we enabled 'Lock Confirmed Sales'
https://github.com/odoo/odoo/blob/863c064fd911cb4eeedad0abec82adb4690128f6/addons/sale/models/sale_order.py#L964
6. `_action_launch_stock_rule()` is invoked, is in charge of creating Pickings for SOs 
https://github.com/odoo/odoo/blob/3be83d363786526fe470e41122169e594b5467fb/addons/sale_stock/models/sale_order_line.py#L303
https://github.com/odoo/odoo/blob/3be83d363786526fe470e41122169e594b5467fb/addons/sale_stock/models/sale_order_line.py#L343-L344
7. But, since `line.order_id.locked` , the system do not create Pickings for the SOs. https://github.com/odoo/odoo/blob/3be83d363786526fe470e41122169e594b5467fb/addons/sale_stock/models/sale_order_line.py#L315-L316
The line was introduced by
https://github.com/odoo/odoo/commit/17bece3e797913bcba8dd7e07fc8541c0a45e3f7

This commit resolves the issue by passing a context key `fsm_create_sale_order=True` when confirming a sales order that is being created from a Field Service task. The `_should_be_locked` method on the sale order is overridden to check for this context key. If the key is present, it prevents the order from being locked within that specific transaction, allowing the stock rules to execute correctly and create the necessary picking. The order will be locked for any subsequent operations as intended.

Tradeoff here;
We are sacrificing the universal application of one feature (automatic lock on confirmed sales order) to fix a critical bug that makes the entire FSM delivery process unusable.

---
EDIT: 
Without this change, all of [test_fsm_stock](https://github.com/odoo/enterprise/blob/17.0/industry_fsm_stock/tests/test_fsm_stock.py)'s test cases that use `_fsm_ensure_sale_order()` will fail if the setting is on. (around ~20 test cases). 

[In the past, similar issue occurred for Subscription Orders, and the PO confirmed that the "Lock Confirmed Order" setting should never affect the subscriptions. ](https://github.com/odoo/enterprise/commit/e4f9d76c0a58f3cc226a2372f3936cea4547312e). This commit takes the same approach to ignore the setting upon SO confirmation. 

opw-4633977
opw-4749653
opw-4880664

Forward-Port-Of: odoo/enterprise#91799
Forward-Port-Of: odoo/enterprise#88855