Partners can now show which companies are linked to them, making it easier to tell whether a partner represents the current company, another company, or an external contact. This helps finance users review company relationships more clearly and avoid confusion when working with partner records.

When a company is created, a partner is linked via a Many2One field from company to partner. But the inverse is also needed to check whether this partner is linked to the current company or another company or is external.

task-5365677

Point of Sale buttons now show a clearer visual difference between active and disabled states. This improves usability in action dialogs, especially in bright environments where low contrast can make choices harder to see.

Before this PR there was a contrast issue between disabled and active secondary buttons in the action dialog.
This was due to a customization where the `btn-secondary`'s default background color was lightened.

To fix this, we used the same lighter background color for disabled `.btn-secondary`, reduced the opacity of its text and desaturated tho whole button for whenever there is color such as the "reward" button. This way we can distinguish between the two states.

A border was added to `.btn-secondary` in order to make the button more visible in light-challenging situations (in broad daylight for example).

task-5186928

| Before | After |
| ------------- | ------------- |
| <img width="1002" height="647" alt="Screenshot 2025-11-06 at 13 17 27" src="https://github.com/user-attachments/assets/cc63d6e1-8587-427e-b5cd-de99e96df8c0" />|<img width="1004" height="645" alt="Screenshot 2025-11-06 at 12 58 07" src="https://github.com/user-attachments/assets/f199fd94-1223-4c6b-869b-e8d66d99bc82" /> |



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The Turkish Nilvera e-invoice integration now has automated tests covering key API interactions and invoice file handling. This helps reduce the risk of regressions and improves confidence that electronic invoicing continues to work reliably for Turkish businesses.

There are no tests for the Turkish e-invoice module. This commit adds that.

Task ID: 4655864

Forward-Port-Of: odoo/odoo#230148
Forward-Port-Of: odoo/odoo#216179

This update adjusts the NSSF (National Social Security Fund) contribution limits in the Odoo Enterprise system to align with the latest regulations as of 2026. Specifically, the lower and upper earnings limits have been revised, impacting the maximum combined contribution an employee can make. This ensures compliance with Kenyan tax laws.

This commit updates the NSSF Lower and Upper Earnings Limits in accordance with the 4th year of implementation of the NSSF Act 2013.

- Set Lower Earnings Limit (Tier 1) to 9,000.
- Set Upper Earnings Limit (Tier 2) to 108,000.
- Resulting max combined contribution is now 6,480.

Task: 5485002

Forward-Port-Of: odoo/enterprise#105019