Add project-wide signal/group managment

[MinofCat]

Describe the project you are working on:

I am working on a platform game

Describe the problem or limitation you are having in your project

There are too many signal and group (which I created through UI and GDscipt) and I cannot manage them.

Describe the feature / enhancement and how it helps to overcome the problem or limitation

Godot should have a tool summarize all the signal/group in the project.

Describe how your proposal will work, with code, pseudo-code, mock-ups, and/or diagrams

With the signal/group is created by UI, it will list in management tool
With the signal/group is created in GS Script, the tool will search all the GDScript and find the commands.

If this enhancement will not be used often, can it be worked around with a few lines of script?

I saw a solution by using grep, but this method is unfriendly and I also don't familiar with Linux
https://www.reddit.com/r/godot/comments/8c03tz/is_there_a_signal_map_that_shows_you_all_your/

Is there a reason why this should be core and not an add-on in the asset library?

It will be use a lot and helpful.

[YuriSizov]

Maybe a mockup would help others see how exactly this will be used and useful?

[Calinou]

See godotengine/godot#24262 where this feature was implemented a while ago, but it wasn't merged due to various technical and design issues (see comments in that PR).

[MinofCat]

For example in my game, It is similar to Megaman, and it has a character like Zero( In funny way). Whenever he appears, he might break something. He just appears in a few level and interact with many object. So I use a lot of signal for him. But if I want to change his behavior (like every time he appears, he distract enemy, so I need to remove/change all the signals).
If I have a tool like Project Manager Tool, I can know exactly how much I need to change, and that help me to prevent bug or zombie code.

Additionally, I think we should have some external tool to manage the project. It will show us the the map of all the scene, signal, group... how many of them, their status,...
I am sorry for the basic proposal

[Calinou]

Closing in favor of #3789, which is more detailed.