Rewrite MedPod bed rest functionality to use custom WorkGivers and JobDrivers

[sumghai]

Describe your idea:

At present, the mod makes pawns seeking medical bed rest to prioritize MedPods over other medical (or regular) beds, by Harmony patching the vanilla WorkGivers/JobDrivers to execute MedPod-specific checks/functions and selectively detouring vanilla code as required.

While this has worked for the most part, there some issues with the current approach:

• Patients currently don't automatically use MedPods for certain untendable conditions, such as missing body parts and food poisoning. The current workaround is to implement a "Prioritize using MedPod" context menu item, although this isn't particularly intuitive for players.
• Patients may (very rarely) get permanently stuck inside MedPods, or hop out halfway during diagnosis/treatment. This is most likely due to the current Harmony patches not fully covering very unusual edge cases, which causes execution to fall back to the vanilla bed rest code with unexpected results.
• Induced Coma hediff used to prevent patients from prematurely leaving MedPod during treatment is a hacky workaround
• Inconsistent behavior for non-colonist pawns (e.g. prisoners, Hospitality mod guests)
• When colony animals are downed, pawns will tend to their injuries first and then haul them to regular animal beds, rather than the expected (and more expedient) behavior of immediately carrying them to VetPods.

Based on initial successes in implementing custom WorkGivers/JobDrivers within existing workTypes for the (WIP) Replimat Cadaver Processor (sumghai/Replimat/issues/43), it may be a good idea to rewrite some of the current Harmony patches into dedicated WorkGivers/JobDrivers with higher priority levels than their vanilla counterparts.

Why do you think your idea would be a good fit for MedPod?:

• Improve robustness and mitigate edge cases in pawn medical bed rest in MedPods
• Flexibility to implement more complex behavior, while safely falling back to vanilla medical beds if no MedPods are available.
• Potentially remove troublesome Induced Coma and related hediffs

What alternatives/workarounds have you tried? Continue to maintain the current Harmony patches, fixing bugs on a piecemeal basis

Declaration

I hereby verify that:

• [x] I have searched the issue tracker and confirmed no-one else has already suggested my idea before
• [x] I understand that my idea will be closed and ignored if I do not fill this form properly, or if the mod author decides that my idea doesn't fit the scope of the mod

[sumghai]

As of 4e99f90, I've successfully implemented the basic use case of ambulatory wounded pawns getting on MedPods themselves.

After a fair bit of testing, I've decided to keep the Induced Coma and Cortical Stimulation hediffs, since trying to patch bed rest toils to completely rely on the patient waiting for the treatment to complete turned out to be unreliable.

[sumghai]

After some testing, 62157b3 also already makes doctors prioritize rescuing colony animals directly to VetPods, rather than the vanilla behaviour of on-the-spot first-aid.

Forbidding or blocking access to VetPods also causes doctors to carry wounded animals back to vanilla animal medical beds, but as soon as a VetPod is available doctors will resume rescuing animal patients to them.

Barring any future bugs, this is pretty much done.