PAK Loading Fixes for MHStories3, Prag, and RE9 (#1577)

* Pragmata PAK support

* MHStories 3 PAK support

* Fix compile error

* Add AoB for `sha3_code_start` for RE9 to get unencrypted PAKs working.

* RE9 workaround/hack to get PAKs loading from `pak_mods`. (hcdd's code.)

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Co-authored-by: hcdd0304 <hcdd0304@proton.me>

Author: Synthlight