fix(container): save default field value when empty on creation

[MyvTsv]

• I have performed a self-review of my code.
• I have added tests (when available) that prove my fix is effective or that my feature works.
• I have updated the CHANGELOG with a short functional description of the fix or new feature.
• This change requires a documentation update.

Description

• It fixes !45954
• When a Fields block is embedded in a ticket's base form and contains a required field with a default value, an error may occur when creating a ticket through a collector.

This is because, when the collector created the ticket, the field’s default value was not saved. The required field therefore remained empty, which caused an error during ticket creation.

This PR fixes this behavior by ensuring that the field’s default value is correctly saved when the ticket is created.