### Context:
In the Manufacturing app, users can create Manufacturing Orders to
create multiple products while assigning a unique serial number to each.
Users can either generate a list of serial numbers starting from a
first serial number, or provide a list of serial numbers themselves.

### Issue:
When providing a list of serial numbers without modifying the first
serial number field (`mrp.production.serials.lot_name`), the inputted
list is not used. Instead, another list starting with the unmodified
`lot_name` is generated and used.

### Cause:
In the `MrpProductionSerials.action_apply` method, the serial numbers
are updated if the first serial number field (`self.lot_name` in the
following code snippet) is left unchanged. This behavior overwrites
the list of serial numbers provided by the user.

https://github.com/odoo/odoo/blob/ac6960dc553088894e688bcc0f4a49245aa02d6c/addons/mrp/wizard/mrp_production_serial_numbers.py#L63-L67

### Steps to reproduce:
1. Install *Manufacturing* (`mrp`)
2. In Settings > Inventory, toggle *Lots & Serial Numbers*
3. Create a product tracked *By Unique Serial Number*
4. Create a Bill of Materials for the product
    - The BoM is required but its content is not relevant.
    Adding a single component with a quantity of one is enough.
5. Update the quantity of the component to be able to produce two products.
6. In *Manufacturing*, create a new *Manufacturing Order*.
    - Select the product and set the quantity to 2, then *Confirm*
7. Click *Generate Serial* or *Produce All*
8. **Do not** modify the *First SN* field, but write two serial numbers
(one per line) in the field below, then click *Apply*.
9. Click the *Serial Numbers (2)* smart button. The serial numbers we
used in step 8 were overwritten by the default *First SN* and its following SN.

### Solution:
This commit addresses the second bug described in https://github.com/odoo/odoo/commit/20158a115ef3dfb9fe2dd5103d3bed7e87e37940 without ever renaming
the serial numbers used for the MO. Now, the `product_id.next_serial`
matches a serial number from the list of provided/generated serial numbers.
The list of serial numbers is sorted to correctly handle cases such as:
```
First SN (self.lot_name) = '0000001'
self.serial_numbers = ['0000003', '0000002', '0000001']
```
In this scenario, we expect the *First SN* of the next MO to start at '0000004'.

The `else` clause of the condition was removed, as it would only be executed
if the `stock.sequence_production_lots` were removed. In that case,
`next_by_code('stock.lot.serial')` would return `False`, preventing
`lot_name` (or `next_serial`) from being updated correctly.

### Reason for second commit

The issue fixed by the first commit was replicated by https://github.com/odoo/odoo/commit/2548fd8d7f3b53a62089ac9122bd17524500ea1a in the subcontracting module (`mrp_subcontracting`). 
The first commit fixes the issue in the Manufacturing app (`mrp`), while the second commit fixes the issue in the subcontracting module (`mrp_subcontracting`). The fix and the test are similar in both commits.

opw-5373745

Forward-Port-Of: odoo/odoo#238678

Steps to reproduce:
===================
-  Add a product categories block with a search bar in the inner content of the block, like "s_product_list".
- Drag a "Search" snippet inside of the block in top of products categories
- Change the layout to "Grid" & Save.
- Type in the search bar to trigger autocomplete suggestions. -> The suggestions appear behind the product categories and are not visible.

Cause:
======
When a searchbar snippet is placed inside a section using grid mode, the autocomplete dropdown was hidden behind sibling grid items. This occurred because the grid layout applies inline z-index to each column (via `_placeColumns` `in grid_layout_utils.js` (See [1])), creating stacking contexts that trapped the dropdown.
So once you change to grid mode layout `_toggleGridMode` function will be triggered which will call  `_placeColumns` that will assign z-index; (See [2])

Solution:
=========
Override the inline z-index on grid items containing a searchbar

[1]: https://github.com/odoo/odoo/blob/d4411c27b469e5dcc526b5b1f8ea4498f2b08567/addons/web_editor/static/src/js/common/grid_layout_utils.js#L225

[2]: https://github.com/odoo/odoo/blob/d4411c27b469e5dcc526b5b1f8ea4498f2b08567/addons/web_editor/static/src/js/common/grid_layout_utils.js#L138

opw-5392011

---
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Forward-Port-Of: odoo/odoo#241478
Forward-Port-Of: odoo/odoo#239607