[PERF] migrate Project parentDisposables to Services

[pq]

Using a Project as a parent disposable can lead to plugins not being unloaded correctly leading to memory leaks. This follows the advice given in the Jetbrains disposer docs and is (I think) consistent with the Dart plugin (@alexander-doroshko?).

This gets us most of the way to fixing #8107 with an open question about AndroidModuleLibraryManager. (Question posed there 👍 .)

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[helin24]

I'm assuming you chose analysis server as the parent disposable since it starts early on in plugin startup? Are there times when the analysis server could restart and cause some things to be disposed incorrectly?

[pq]

Great question. I chose it because it's a projectService and that seems to be the recommended place to hook in to disposal. I don't think a server restart will have any effect on this as a service but will do a bit more testing.

Thank you!

(EDIT: server restart does not appear to impact the service lifecycle.)

[helin24]

Ah yes, that makes sense. Thanks for clarifying my understanding :)

[pq]

And thanks for asking! I'm just figuring it out too and definitely don't want to get it wrong!