**Steps to reproduce:**
- Install eCommerce app
- Go to the shop of the website
- Activate the editor
- Click on 'New' in the top right
- Create new product with image
- Image is automatically converted to 1920x1920 in webp format
- Thumbnails have low quality when computed in JS (visible artifacts such as dotted diagonal lines and aliasing), especially on Firefox

**Issue:**
For other image formats, the resizing is done in the backend and use a specific downsampling algorithm (Lanczos) with PIL to improve the output quality. But as we are moving to use .webp format as the default, which is processed directly in JS for security reasons (and browser dependent), this algorithm is not applied anymore (which leads to some visual degradation in the thumbnails).

WebP format is not supported on the python side due to `Pillow` dependency to `libwebp` which is considered unsafe at the moment.

Using higher resolution images and downsizing them using css sometimes fix the issue, but it mainly works on Firefox, which seems to apply a different downsampling with css and with canvas drawing.

**Fix:**
Implemented Lanczos resampling for the webp format when processed in the browser.

related : https://github.com/odoo/odoo/commit/d1292a96a62b18a88a852c69ed7732d16ae0344e

Not sure about the licensing needed, as I used this old implementation as a reference: https://github.com/mudcube/Lanczos.js

opw-4561958

---
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Issue Before This Commit:
=======================
When a subcontractor (portal user) tries to open a picking from the Manufacturing orders section in the portal view, the page appears blank with no data loaded on the frontend, while in the the backend logs show read Access Error is raised on the `product.supplierinfo` and on `product.template.attribute.value` models.

Steps to Reproduce:
=======================
-Install  `MRP` and `Purchase` modules, and enable Subcontracting.
-Create a product attribute with values and `variant creation` set to `Never`.
-Create a product and Assign the created attribute to the product’s attributes.
-Create a portal user and grant portal access.
-Create a BOM for the product, set it for subcontracting, and assign the portal
 user as a subcontractor.
-Create a Purchase Order for a subcontracted product linked to that vendor.
-Log in to the portal view as the portal user and open Manufacturing Orders.
-Try to open the related picking and the page fails to load and appears blank.

Cause of the issue:
=======================
In this [PR](https://github.com/odoo/odoo/pull/177390), The `_compute_description_picking` method was extended to include vendor product code and product name using the `selected_seller_id` field, and  the product attribute values using  the `product_no_variant_attribute_value_ids` field. Since `selected_seller_id` points to `product.supplierinfo` model and `product_no_variant_attribute_value_ids` points to `product.template.attribute.value` model, `group_portal` do not have read access to these models causing access errors when the picking description is computed, so the page appears blank while opening the picking.

After This Commit:
=======================
The `_compute_description_picking` method now uses `sudo()` to safely access `selected_seller_id` and `product_no_variant_attribute_value_ids` fields, allowing portal users to compute stock move descriptions without encountering access errors. This prevents the page from appearing blank when opening picking in the portal without granting direct model access.

Task-4958070

When selling a bom kit that have some components that applies on specific variants only, the picking was not correctly created. It would only take one kit variant into account, even if you sold 2 kits with different variants.

Steps to reproduce:
-------------------
* Create a product P
* For product P, create an attribute with type "No variant" and values V1 and V2
* Create a BoM Kit for product P, with 3 components C1 C2 and C3
  - C2 applies only for variant V1
  - C3 applies only for variant V2
* Create a POS order with 2 lines of product P:
  - 1 with variant V1
  - 1 with variant V2
* Validate the order and check the created picking
> Observation: Only C1 and C2 are in the picking, C3 is missing

Why the fix:
------------
When creating the picking, the code was grouping the order lines by product only, and not by product variant. Therefore, the 2 lines would be grouped together, and only one of the variant-specific components would be taken into account.

opw-5051289

Forward-Port-Of: odoo/odoo#237796
Forward-Port-Of: odoo/odoo#235528