feat: migrate field (component field or input) to signal

[eneajaho]

• Per file and per component and per field
  ng g ngxtension:convert-di-to-inject --path $FilePathRelativeToProjectRoot$ --field $SelectedText$

Same thing can be done using vscode tasks: https://code.visualstudio.com/docs/editor/variables-reference#_predefined-variables

This can be a one-click thing in webstorm where you select the field and click the run button in the top bar run configurations.

The migration will follow this steps:

• Check if it's already a signal -> skip
• convert the field to signal
• find the usages and if it's being assigned use set or update depending on the use case
• replace only reads to include () -> we already do this for signal inputs
• replace the template references -> we already do this for signal inputs

At this point we can easily migrate to signals by select a field and running a migration schematic

This should work for most of the cases and fail for some advanced ones, but we're not reaching for perfection here 😄