Saving blockair/blockairh is nice because RecalculateBlockAirMaps uses the sim rng, which means the sim rng would get advanced in Simulation::Load. Also rename RecalculateBlockAirMaps to ApproximateBlockAirMaps because that's what it is, an approximation, and it's needed only if there are no block air maps in the save.
Simulation::frameCount keeps track of frames elapsed since the beginning of the simulation, zeroed at clear_sim. It overflows when it reaches the 64-bit limit, which means anything that depends on it should either handle this, or not fail catastrophically. sandcolour (the only thing that depends on it as of now) is a good example of the latter: sandcolour has a periodicity of 360 frames, which means that there is one sandcolour period that is cut short by the overflow. This is not "handled" (the period is cut short, which is detectable by users) but is not catastrophic either (it's not a big deal, and it won't ever happen unless someone hacks the save).
Also restrict saves with determinism data to 98.0.
Achieved by adding a new element property called CarriesTypeIn, whose bits signal to save loading code which properties of particles of the element class in question carry element IDs. The bits in this property are numbered the same way as sim.FIELD_* constants for consistency. One would signal from Lua that a custom element carries element IDs in its tmp like this:
elem.property(id, "CarriesTypeIn", 2 ^ sim.FIELD_TMP)
"Carrying an element ID in a property" is to be interpreted as follows: the property is treated as a combination of a PMAPBITS-bit (so, currently 9-bit) unsigned integer lower part holding an element ID and a 32-PMAPBITS-bit (so, currently 23-bit) signed integer upper part holding whatever makes sense for the element. CONV, for example, uses this signed integer in its ctype as the extra "v" parameter for particle creation.
Also replace a few rename calls with RenameFile calls. Old code doesn't expect rename to overwrite existing files without question, when it in fact can.
These are the only bit of shared state between the Request user thread and RequestManager that aren't covered by RequestHandle::stateMx. The problem was that they were not covered by anything, which meant that they were not guaranteed to be coherent between threads.
Namely: no, yes, and yes and ask at startup.
The install_check option is thus replaced by the can_install option. -Dinstall_check=true maps to -Dcan_install=yes_check, while -Dinstall_check=false maps to -Dcan_install=yes. -Dcan_install=no is new and is recommended for downstream packaging, where -Dinstall_check=false was historically used.
Also improve error messages about bad configuration here and there and scatter configuration code in subdirectories, where they can be closer to their areas of effect.
... while retaining all the functionality of stamps.def.
Also fix stamp names encoding only 32 bits of the timestamp, migrate from stamps.def to stamps.json if the latter doesn't exist, delete both on migration to the shared data directory, rescan stamps at startup, and make rescanning a painless process in general by removing invalid entries and adding missing entires at the beginning of the list.
Request ownership is no longer flaky. Requests are now owned by the code that makes requests, and Requests and the RequestManager co-own RequestHandles. RequestManager disowns a RequestHandle if it's done with it or if Request code reports that it's no longer needed.
All libcurl code has been moved to RequestManager. This is nice because once NOHTTP is removed, we can add any number of RequestManager implementations, for example one for Android.
Client outliving RequestManager is still a problem, this will have to be addressed later.
Some operator[]s that know the size of the container they wrap like to assert(index >= 0 && index < size), which is bad for us because we sometimes use &container[size]. This is not undefined behaviour until that pointer is dereferenced, but certain operator[]s choose to ignore this fact and err on the side of caution. The solution is to use &container[0] + size instead of &container[size].
Also fix font editor builds on windows and add more font editor builds to the ghactions workflow.
Funny, we don't really need resource.h anymore. The resource compiler does, but we don't.
