Electronic invoicing options are now selected more reliably based on each customer’s country and Peppol eligibility. Italian customers will default to the local FatturaPA format, and users will see fewer irrelevant Peppol options when their company cannot use them.

### Commit 1: [IMP] l10n_it_edi: add FatturaPA as the preferred edi format for IT partners
Add FatturaPA as the preferred EDI format set by default on Italian partners.

task-no

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### Commit 2: [FIX] account_\*,l10n_\*: EDI formats computation fixes
1. Before this commit, there was multiple lists of UBL/CII formats
that needed to be maintained. This was error prone because each implementation
needed to overrive each of these lists. We now have one dict with all formats
informations that is parsed in different ways depending on the need.
(By Country, Peppol compatible, ...)

2. Before this commit, if a country had two possible UBL/CII formats, one
always override the other, we now have the possibility to have multiple formats
per country and set a priority on them (trough a sequence number).

3. Before this commit, we maintained a list of NON-PEPPOL formats, this had multiple
drawbacks: it's hard to maintain, error prone, unecessary negation that made condition
tricky to understand. We now set a value on the dictionnary of UBL/CII formats that marks
the format as compliant with Peppol Network.

task-4240924

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### Commit 3: [IMP] account_peppol: refine displayed EDI formats and sending methods in partner form
Make the displayed information on partner form more relevant:
- the sending method "by Peppol" is no longer visible when the current company can't
enable Peppol (for example an US company).
- the EDI formats displayed when "by Peppol" is the preferred sending method are
now only EDI formats supported by the Peppol Network.

task-4240924

Inviting someone as a follower in Mail will no longer send an invitation notification automatically. This reduces duplicate emails when users are adding followers before sending them an actual message.

Technical users can now import attachments while preserving their links to related records and fields. This makes controlled attachment data migrations easier from the debug-only technical menu.

readonly=True on `res_model`/`res_field`/`res_id` of ir_attachment making these fields not importable. Attachment menu is only accessible in debug mode in the technical menu anyway. Then we suppose that user in attachment views understand what he does (hopefully).

task-4252555

The Point of Sale apps have been adapted to meet Belgian restaurant certification requirements. This helps restaurants using Odoo in Belgium stay compliant while continuing to use related POS features such as staff login, loyalty, restaurant workflows, and self-ordering.

pos*: point_of_sale, pos_hr, pos_loyalty, pos_restaurant, pos_self_order

In this commit, we adapt the point of sale modules to be compliant with the belgian restaurant certification.

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The mail search panel was cleaned up by removing an unused setting that had no effect on how it appeared or behaved. This keeps the code simpler and easier to maintain without changing the user experience.

Purpose of this commit:
This commit removes the unused `className` prop from the SearchMessagePanel, 
as it was never utilized in the component's template.

Online food orders from UrbanPiper, Swiggy, and Zomato now show merchant-paid GST taxes on order lines when the tax rate is not the aggregator-paid 5% GST. This helps merchants in India better understand and reconcile taxes they are responsible for collecting and paying.

**=pos_urban_piper, pos_urban_piper_swiggy
After this commit:
- In India there is a special case that  5% GST is collected by the aggregator and paid by the aggregator directly but other than this like 12% or 18% GST is collected by the merchant and paid by the merchant itself.
- This commit targets to display taxes in the order line if they are other than 5% GST.

task- 4190283

Point of Sale has been updated to better meet Belgian restaurant certification requirements. Businesses can now use QR code ordering without requiring online payment, and product prices can be adjusted directly in the cart where permitted.

pos*: pos_blackbox_be, pos_iot, pos_restaurant_preparation_display

In this commit, we adapt the point of sale modules to be compliant with the belgian restaurant certification.

A summary of the changes since last version:
- QR ordering: QR code ordering is available without online payment. Just a simple ordering configuration.
- Price can be changed: The price of a product can be changed in the cart.

Signing requests now automatically select the partner linked to the record as the default signer. This reduces manual selection work and helps send documents to the right person more consistently.