**Current behavior:**
If we have a picking batch with some pickings all for the same product, while enforcing mandatory scans on source location, products, and destination location, there is some unexpected behavior if a different destination barcode is scanned after the similar-product pickings have all been scanned.

**Expected behavior:**
With this specific configuration, pickings with the same product should all be changed when a different destination is scanned.

**Steps to reproduce:**
1. In the Internal Transfers picking type, configure the barcode settings like so:
     `Source Location: Mandatory Scan`
     `Product: True`
     `Destination Location: After each product`

2. Create some new internal location (e.g., .../Stock/shelf)

3. Create a new batch picking with 2 internal transfer pickings for the same product

4. Go to the batch operation barcode menu, select the created batch picking

5. Scan the source location, scan the first product code and then manually add the second picking quantity with the add quantity button, scan the newly created internal location

6. Observe that the last picking destination location has changed and the first has not- furthermore trying to change the second's destination location via scan does not work (manual changes via the edit button/form still possible)

**Cause of the issue:**
The method of changing destination does not account for this setup, so there is no specific handling for it. Only the selected line will be modified by a new destination scan.

**Fix:**
Extract the line modification code into a new function and override it in the batch_picking module to change the entire current batch of lines that have been scanned (that all have the same product).

opw-3733870

When user clicks on contracts smart button in application and if application has
two contracts (one archived and one active), a traceback will appear.

Steps to reproduce the error:
- Install "hr_contract_salary" module
- Go to Recruitment > Applications > All Applications > Create new application >
  Generate Offer > Select Contract Template > Send By Email > Send
- Click on Offers > Salary Configurator > Fill all required fields >
  Review Contract & Sign > Validate & Send Completed Document
- Open that application > Contracts > Create new contract > Save
- Archived one contract > Click on Contract smart button

Traceback:
```
ValueError: Expected singleton: hr.contract(27, 29)
  File "odoo/http.py", line 2253, in __call__
    response = request._serve_db()
  File "odoo/http.py", line 1829, in _serve_db
    return self._transactioning(_serve_ir_http, readonly=ro)
  File "odoo/http.py", line 1849, in _transactioning
    return service_model.retrying(func, env=self.env)
  File "odoo/service/model.py", line 134, in retrying
    result = func()
  File "odoo/http.py", line 1827, in _serve_ir_http
    return self._serve_ir_http(rule, args)
  File "odoo/http.py", line 1834, in _serve_ir_http
    response = self.dispatcher.dispatch(rule.endpoint, args)
  File "odoo/http.py", line 2059, in dispatch
    result = self.request.registry['ir.http']._dispatch(endpoint)
  File "odoo/addons/base/models/ir_http.py", line 220, in _dispatch
    result = endpoint(**request.params)
  File "odoo/http.py", line 740, in route_wrapper
    result = endpoint(self, *args, **params_ok)
  File "addons/web/controllers/dataset.py", line 42, in call_button
    action = self._call_kw(model, method, args, kwargs)
  File "addons/web/controllers/dataset.py", line 34, in _call_kw
    return call_kw(request.env[model], method, args, kwargs)
  File "odoo/api.py", line 458, in call_kw
    result = getattr(recs, name)(*args, **kwargs)
  File "home/odoo/src/enterprise/saas-17.2/hr_contract_salary/models/hr_applicant.py", line 59, in action_show_proposed_contracts
    "res_id": self.env['hr.contract'].search([["applicant_id", "=", self.id], '|', ["active", "=", False], ["active", "=", True]]).id,
  File "odoo/fields.py", line 5182, in __get__
    raise ValueError("Expected singleton: %s" % record)
```

https://github.com/odoo/enterprise/blob/504b3c66a9a8d142b89f9c873675ec65fdb43dd0/hr_contract_salary/models/hr_applicant.py#L59
Here when application has two contracts (one is archived and one is active),
So when it tries to access the id of 2 records.
It will lead to the above traceback.

sentry-5350130147

Forward-Port-Of: odoo/enterprise#62627

Description of the issue/feature this PR addresses:
If the user has two invoices/bills selected where one falls within the parameters of a discounted payment and the other does not, the calculated payment total and payment difference will be wrong.

Current behavior before PR:
If I have two Bills, both for $25.00 where one falls within the parameters of a discount for 2% in 10 Days and the other doesn't, and I select both of them and click register payment, and the select "Group Payments" (group_payment), the "Amount" (amount) will be $0.50 and the Payment Difference (payment_difference) will be $49.50. 

Desired behavior after PR is merged:
In the same scenario, I would expect the "Amount" to be $49.50 and the "Payment Difference" to be $0.50


To Reproduce:

- Create Payment Term "2% 10, Net 30" this payment term should be configured to have a discount of 2% if paid in the first 10 days, and then 100% of the bill is due in 30 Days. 
- Create two Purchase Orders (doesn't matter which products you purchase), receive products, and create bills. Make sure one has the new payment term you created and its bill date puts it within the discount parameters. The other bill should either have a different payment term that doesn't have a discount or the same term but not be within the parameters to have the discount apply (bill is older than 10 days in this case)
- Go to Accounting --> Vendors --> Bills and select both of these new bills and click "Register Payment"
- In the wizard, click "Group Payments" and you will see the amount and payment difference are incorrect.

**This process can also be done with sale orders instead, you will get the same result with two invoices for customers.

---
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