Document script engine: Transfer Resarch from SkyTemple SSB Debugger & PsyCommando's notes

[theCapypara]

In early 2020 I made a lot of research based on Psy's research on the game's script engine. A lot of this made it into SkyTemple's script engine debugger and also pmdsky-debug.

Some of the most important undocumented things are related to the script engine thread state structs and other entities (actors, events, map, objects, performers, global script):

https://github.com/SkyTemple/skytemple-ssb-emulator/blob/main/src/script_runtime.rs
https://github.com/SkyTemple/skytemple-ssb-debugger/blob/master/skytemple_ssb_debugger/model/script_runtime_struct.py
https://github.com/SkyTemple/skytemple-ssb-debugger/blob/master/skytemple_ssb_debugger/model/ground_state/global_script.py
https://github.com/SkyTemple/skytemple-ssb-debugger/blob/master/skytemple_ssb_debugger/model/ground_state/actor.py
https://github.com/SkyTemple/skytemple-ssb-debugger/blob/master/skytemple_ssb_debugger/model/ground_state/event.py
https://github.com/SkyTemple/skytemple-ssb-debugger/blob/master/skytemple_ssb_debugger/model/ground_state/map.py
https://github.com/SkyTemple/skytemple-ssb-debugger/blob/master/skytemple_ssb_debugger/model/ground_state/object.py
https://github.com/SkyTemple/skytemple-ssb-debugger/blob/master/skytemple_ssb_debugger/model/ground_state/performer.py

Additionally I took notes from Psy and made my own, mostly connecting the dots between his research and traces I did with the emulator integration.

I uploaded all my notes I have here: https://github.com/theCapypara/pmdsky-ground-state-notes

[theCapypara]

Some more notes start before and after here: https://discord.com/channels/710190644152369162/712341699292037121/1194771802916917331

[Adex-8x]

To add onto this, Psy's notes: https://github.com/PsyCommando/pmd_2_doc/tree/main/doc/script_engine