Move CoreDbg into Lua API

[Aurumaker72]

Rationale

The CoreDbg GUI isn't useful.

Proposal Summary

We should instead just expose some debugger functionality functionality to Lua.

The basic idea is as follows:

---Calls the function `f` every instruction.
---If `unregister` is set to true, the function `f` will no longer be called when this event occurs, but it will error if you never registered the function.
---@param f fun(context: CPUContext): nil The function to be called every instruction.
---@param unregister boolean? If true, then unregister the function `f`.
---@return nil
function emu.atinstruction(f, unregister) end

---@return boolean # Whether the emulated processor is currently paused.
function coredbg.paused() end

---Pauses the emulated processor.
function coredbg.pause() end

---Resumes the emulated processor.
function coredbg.resume() end

---Resumes the emulated processor and advances it by one instruction, then pauses again.
function coredbg.step() end

Open Questions

No response

Technical Considerations

No response