Case transformation configuration

[Schottkyc137]

As of 4f20cbd it is possible to enable case transformations for completions. So instead of completing STD_LOGIC_VECTOR, the user can now choose between lower case (std_logic_vector), upper case (STD_LOGIC_VECTOR) or pascal case (Std_Logic_Vector). Yet, for productive use, not all completions should be transformed in the same manner. For example:

• constants are usually upper case constant FOO_BAR : std_logic_vector
• keywords are lower case whereas identifiers are pascal case
• the language server should potentially only change third-party code

I would like to discuss the most suitable configuration option. As an example:

[preferred_case]
# This would contain constants and generics
constant_like = "upper"
keywords = "lower"
# Name subject to change
signals_and_variables = "pascal"

There is also the question as to how granular these options should be. I.e., should it be possible to modify every single keyword? How are multiple categories (i.e., signals and variables) aggregated?