[TASK] Index also documentation from Other manuals and Exceptions

[soee]

Before this changes we were indexing only documentations from 3 folders:

• ^m/
• ^c/
• ^p/

which were configured through services.yaml file and the docsearch.allowed_paths setting.

There are though important documentation files inside other and typo3cms folders.

This commit updates the allowed and excluded paths for indexing (services.yaml):

parameters:
    docsearch.allowed_paths:
                - ^m/
                - ^c/
                - ^p/
                - ^other/
                - ^typo3cms/
    docsearch.excluded_directories:
                - draft
                - extensions

and introduces special handling for importding documentation of exceptions from typo3cms/exceptions folder, where the folders structure is shorted, and has to be handled different way to have proper slugs, paths etc.