Achieve complete understanding of the design and mechanism of the imenu and speedbar code base.

Goal: enhance ability to piggyback code navigation using these facilities.

• learn how these facilities are used to detect definitions in various programming languages:
• detect problems of detection in those programming languages if any and try to overcome them
• identify packages that may help and integrate them inside PEL
• allow the use of LSP-based backed but don't require them, making LSP a possible enhancement but allow using Emacs without it in case it is too expensive