This fixes delivery method selection so sales orders can use shipping methods shared across companies when no company is assigned. It also changes shipping update errors to appear as visible notifications instead of dialogs that could be hidden behind the shipping wizard.

Description of the issue/feature this PR addresses:

Current behavior before PR:

Desired behavior after PR is merged:




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This fixes a timing issue that could cause the export screen to fail when default export fields loaded before the model field details were ready. Users should see more reliable exports with fewer unexpected errors.

Customers can now choose a delivery carrier during website checkout without errors, and the selected carrier is correctly saved on the sales order in the backend. This helps prevent checkout disruption and ensures order fulfillment teams see the right delivery method.

Description of the issue/feature this PR addresses:
We were unable to pick a carrier without a traceback and once the carrier was selected, the SO in the backend didn't have the carrier value.

Current behavior before PR:
The carrier of the new SO generated from the website is not set and we have multiple traceback.

Desired behavior after PR is merged:
There is no more traceback and once we select a carrier from the website, the carrier is set in the backend too.



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This update ensures project tasks created from sales orders use the same company as their project, improving consistency in multi-company setups. It also prevents incorrect access errors when viewing followers on records from allowed companies.

Description of the issue/feature this PR addresses:

Current behavior before PR:

Desired behavior after PR is merged:




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This change ensures the Gantt view sends date and time information to the server in the expected format when checking availability. It prevents crashes in scheduling-related views and keeps responsibility for valid data formatting on the client side.

The string received by `gantt_unavailability` was not in a valid
datetime format for the server, this would cause a crash if the code was
only using `fields.Datetime.from_string` in order to convert the
received string.

To avoid this crash https://github.com/odoo/enterprise/commit/52228b9cfa16126e059c53fe436d3745fc71bdf1#diff-ea773c599012668663043126fb43b754R238 introduced a work arround
(using `.replace('T', ' ')`).

This work arround cannot be considered valid as it is the client
responsibility to send a valid information to the server (in our case a
valid datetime string).

This fix reuses the `convertToServerTime` method defined in
`gantt_model.js` in order to convert the datetime in the right format when
asking for `gantt_unavailability`.

It should be noted that there are already a number of functions in order
to convert from and to dates, times, datetimes and moment.js objects,
those are defined in `time.js` and should probably be considered as
replacements for the custom `convertToServerTime` method.

This update adapts several Odoo Enterprise apps to underlying platform changes designed to improve performance and reliability. It helps accounting, documents, CRM, helpdesk, HR, payroll, and related workflows continue running smoothly after the core system update.

Adapt to odoo/odoo#35659.