Docs: Update YAML planning guide (ArchipelagoMW#1845)

* [Docs] Update YAML planning guide

Changed wording for items accessibility to describe how it actually works. Reordered settings such as local_items and start_location_hints to match their order in templates. Fixed some grammatical errors.

* Fix typo

Co-authored-by: Zach Parks <[email protected]>

* Update doc

Moved `accessibility`, `progression_balancing`, and `triggers` to game sections instead of root sections and reworded description accordingly. Updated version number. Fixed `progression_balancing` values in example YAMLs.

* Indented trigger to be part of ALTTP

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Co-authored-by: Zach Parks <[email protected]>