refactor: provide reusable formly configs

[MaxKless]

PR Type

[ ] Bugfix
[ ] Feature
[ ] Code style update (formatting, local variables)
[x] Refactoring (no functional changes, no API changes)
[ ] Build-related changes
[ ] CI-related changes
[ ] Documentation content changes
[ ] Application / infrastructure changes
[ ] Other:

What Is the Current Behavior?

Currently, the PWA code contains many repetitions of the same formly field configurations. For example, the firstName field is present in the registration page, each address form and the account page. This can lead to some inconsistencies (see #997) and to lots of repetition when adjusting a field configuration.

What Is the New Behavior?

This PR attempts to solve this problem by introducing a central point of contact for interacting with reusable field configurations, the aptly named reusable-formly-field-configurations.service.ts (name WIP 😸).
It can read a list of predefined configurations and then lets you retrieve a field configuration service by id (for example firstName) anywhere you inject the service. This leads to less repetition.

ToDo

• How to handle minor changes to a field? Maybe an override argument that performs a deep merge for the selected properties (like ngrx entity partial updates)
• How to integrate with address form configurations
• Central point of customization via transform method in service or extension that does the same?
• let field configuration overwrite key or let user overwrite key?
• write schematic for adding a new shortcut
• write documentation
• automatic documentation from folder
• check correct documentation in pipeline
• helper eslint rules? (sorting module entries, key not included in configuration, ...)
• EXTENSION FOR COMPLETE AUTOMATION?!
• adjust project structure rule configuration for .configuration.ts files
• check override functionality on arrays
• write tests
• Decide on naming & folder structure -> adapt docs in case of name changes
• extension for field groups?
• add project structure tests for new functionality
• write schematic for adding a new form config

Does this PR Introduce a Breaking Change?

[x] Yes
[ ] No

Other Information

AB#74369