[REF] survey: on survey.{question,user_input.line}, make type and field names match

PURPOSE

As new features are about to land in survey, notably live interactions [1]
and new survey building [2] performing a pre cleaning is necessary. In this
PR we clean survey models by: removing unnecessary fields, cleaning some code
and finally renaming models.

SPECIFICATIONS

To better understand question type and their input type, we update some of
``survey.question`` ``question_type`` keys :

  Type----Old type-----New type

  text----free_text----text_box
  char----textbox------char_box

Untouched question types: ``numerical_box``, ``date``, ``datetime``,
``simple_choice``, ``multiple_choice``, ``matrix``. Those are already
understandable.

Then ``survey.user_input.line`` ``answer_type`` keys are also updated to
match their question type counterparts

  QuestType--------Old type-----New type

  text_box---------free_text----text_box
  char_box---------text---------char_box
  numerical_box----number-------numerical_box

Then ``survey.user_input.line`` fields used to store the value are updated to
propagate the new naming

  AnswerLineType----Old field----------New field

  text_box----------value_free_text----value_text_box
  char_box----------value_text---------value_char_box
  numerical_box-----value_number-------value_numerical_box

Untouched answer types and field storing value: ``date``, ``datetime`` still
refer to same question type and use value_date / value_datetime fields.
``simple_choice``, ``multiple_choice`` and ``matrix`` still use ``suggestion``
answer type and ``suggested_answer_id`` (+ ``matrix_row_id``) to store link
to ``survey.question.answer`` records.

LINKS

[0] Related to Task ID 2061901 (survey models cleaning and preparation)
[1] Task ID 1972640 (live interactions)
[2] Task ID 2119587 (new frontend for building surveys)

PR #40765