Currently an error occurs when auto vacuum tries to clear documents linked to `sign_document`.

**Steps to replicate:**
* Install `documents_sign` with demo data.
* Go to documents > Move Employment contracts to trash
* Trash > Try to to delete employment contract you will see error in terminal.

Similarly error will be produced by the Auto-Vacuum process when it attempts to delete it after the configured deletion delay.

**Error:**
`ForeignKeyViolation: update or delete on table 'ir_attachment' violates foreign key constraint 'sign_document_attachment_id_fkey' on table 'sign_document' DETAIL:  Key (id)=(1164) is still referenced from table 'sign_document'.`

**Root cause:**
* At [1], the `sign.document` model was introduced, which prevents the deletion of sign documents. As a result, attempting to delete them due to [2] will cause an error.

**Solution:**
* Update the `_get_gc_clear_bin_domain`  to ensure that the Auto-Vacuum process skips sign documents.
* This will still throw an Validation and ForeignKey error as expected when the user tries to delete it from the GUI letting them know it cannot be deleted.

[1]:
https://github.com/odoo/enterprise/commit/4254542e8fb4ce3b2b9b46c624d86f7fcac8df7b#diff-deebbcccf829fd1804d145c5c7140b482801644bd948639f77caa310b18b8120 
[2]:
https://github.com/odoo/enterprise/blob/828d47f9ad1d5e396b074c404287799574a6d692/sign/models/sign_document.py#L44

sentry-6842360375

Forward-Port-Of: odoo/enterprise#93818

Versions
--------
- 16.0+

Steps
-----
1. Have 2 eCommerce sites;
2. have a user with an open cart in both sites;
3. have a reward applied in one or both of carts;
4. have a fiscal position applicable to the user's address;
5. change the user's country to one with a different fiscal position.

Issue
-----
> ValueError: Expected singleton: sale.order(1, 2)

Cause
-----
As of commit ede8846987a98, fiscal positions get recomputed on address changes. When a fiscal position changes, the `_recompute_prices` method gets called on all open carts.

This method does not include an `ensure_one` check, so it should be able to handle multiple sales orders.

However, the `sale_loyalty` override will call `_update_programs_and_rewards` on `self` if any reward line is encountered. This method does have an `ensure_one` check, leading to the error.

Solution
--------
Rewrite the override as a loop, so it can handle multiple records in `self`.

opw-5017669

Forward-Port-Of: odoo/odoo#224225

Currently an error occurs when creating the attendee records.

Steps to Reproduce:

 - Install the `website_slide` module.
 - Go to `Reporting` > `Attendees`.
 - Go to either the `Graph or Pivot View` and click on any `count` value.
 - Open any attendee record and click on `New`.

`SyntaxError: syntax error at or near ")"
LINE 18: WHERE SCP.id IN ()
^`

This error occurs when creating an Attendee record. The _compute_next_slide_id
method runs every time the record is accessed, which causes the error [1].
As clearly mentioned in [this commit](https://github.com/odoo/odoo/commit/fd2fb88bb155b680147313433d22a2b7388c902c#diff-1ee3fce434db0c4e897973eebf5c1be501196cbd413e6c250ecc973238f939b9L292-R326), when a compute method is declared
without the @api.depends(...) decorator or with no actual dependencies,
the computed field will still be initialized when creating a new record
from a form view.

This commit ensures that when the compute method runs and the record
has not been created yet, the next_slide_id is set to False.

[1]:- https://github.com/odoo/odoo/blob/9f18013bc05e6657f5d41c05931fcdafad827d54/addons/website_slides/models/slide_channel.py#L91

sentry-6465821899

---
I confirm I have signed the CLA and read the PR guidelines at www.odoo.com/submit-pr

Forward-Port-Of: odoo/odoo#217104

Currently, an error occurs when enabling `Can Create` in Studio for a Website
Live Chat channels.

**Steps to reproduce:**

- Install the `im_livechat` and `web_studio` modules.
- Go to `Live Chat`, create a new channel, then return to the Live Chat channels
  view and open the newly created channel in kanban view.
- Open `Studio` and enable `Can Create`.

**Error:**
```
SyntaxError: syntax error at or near ')'
LINE 12: WHERE discuss_channel.id IN ()
```

**Root Cause:**
At [1], an `SQL query` is executed with `self.ids`, when `self.ids` is `empty`, this
leads to an `error`.

**Fix:**
This commit prevents the error by updating `_get_last_messages` to check for `empty self.ids` 
and return an empty recordset early and also updates `_compute_duration` to safely handle 
cases where `record.create_date` is `False`.

[1]:
https://github.com/odoo/odoo/blob/70a7babcc830f72bd069a5bb1504748363e4e848/addons/mail/models/discuss/discuss_channel.py#L1404-L1421

sentry-6861438710