* Use a singleton for instruction decoding
* Use singleton class
* Patch `EXTRQ`
* Fixup signal context functions
* Update CMakeLists.txt
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Co-authored-by: georgemoralis <giorgosmrls@gmail.com>
* cpu_patches: Patch just-in-time using illegal instruction handler.
* core: Add common signal dispatch system and use for on-demand TCB patches.
* page_manager: Re-add userfaultfd implementation.