Currently, a task remains linked to its original sales order even when it has no sales order item. This prevents users to not bill a task and temporarily detach it from a sales order until it can be linked to a new one.

**Steps to produce:**
* Install Sales, Project
* Products > Virtual Home Staging > Create On Order > Project and Task
* Create and confirm quotation with that product.
* Tasks > Empty Sale Order Item Field

**Observed Behavior:**
* Sale Order is still linked to the task despite sale order line has been unlinked from that task.

**Root cause:**
* Compute method [1] only detaches the sale order if the customer has been changed.

**Solution:**
* Only detach the sale order when there are no sale order items and the record is not a field service task.
* Field service tasks should always keep the sale order linked so materials can still be added to the existing sale order, even when the task is non-billable (i.e., no sale order line is linked). This logic is handled by the compute override at [2], which reassigns the sale order when needed.

[1]:
https://github.com/odoo/odoo/blob/3f4e45ecaca46a98c904536658728a1f1571bdbd/addons/sale_project/models/project.py#L916-L935 
[2]
https://github.com/odoo/enterprise/blob/6658581828dcdc43ffc5823814a05cb936cd0500/industry_fsm_sale/models/project_task.py#L178-L194

Related community PR: https://github.com/odoo/odoo/pull/241446

opw-5215989

Forward-Port-Of: odoo/enterprise#107716
Forward-Port-Of: odoo/enterprise#103487

Steps to reproduce:
- Have facturae modules installed
- Generate invoice with any amount
- Send to Facturae

Issue:
Resulting XML has 8 digits after the decimal point on several fields, such as unit price, gross amount, and total cost.

When trying to validate such an XML, this results in validation error: "RCF06001: En facturas emitidas en euros, alguno de los importes de las líneas tiene más de dos decimales (regla 6a del anexo II de la Orden HAP/1650/2015)."

According to regulation HAP/1650/2015 [1]: For invoices issued in euros, it will be validated that the total line amounts related to the total cost are numeric and rounded, according to the common rounding method, to two decimal places.
This commit introduces dynamic decimal precision: 2 places for EUR and 8 places (the previous default) for other currencies.

[1] https://www.boe.es/diario_boe/txt.php?id=BOE-A-2015-8844
Machine translated [BOE-A-2015-8844 (1).pdf](https://github.com/user-attachments/files/25345382/BOE-A-2015-8844.1.pdf)


opw-5927356

Forward-Port-Of: odoo/odoo#248882

**Steps to Reproduce:**
1 - create an employee in Belgium company with hourly rate 20.62 and 40h/week working schedule 2 - Set 10 paid time off to this employee
3 - Set 2000 euros in recovery amount holiday n-1
4 - Set 10 days in recovery day holiday n-1
5 - Employee takes 5 paid time off in February and 5 in December 6 - Do one payslip for this employee for February  and validate it 7 - Do one payslip for this employee for December

Current behaviour :
- the holiday n-1 amount for February = 824.80
- the holiday n-1 amount for December = 742.32

Expected behaviour :
- the holiday n-1 amount for December should be 20.62 (hourly_rate) * 5 (days) * 8 (hours) = 824.80

**Reason**
- The daily recovery amount was calculated using hardcoded standard working hours (38h/week) instead of the employee's actual schedule (40h/week), causing an incorrect deduction rate for non-standard schedules.

**Solution**
- Replace the hardcoded reference with the actual hours per week from the employee's resource calendar to ensure the correct hourly rate is applied.

Forward-Port-Of: odoo/enterprise#107858
Forward-Port-Of: odoo/enterprise#106205