This adds avoid_dynamic_calls to the list of lints, and fixes all instances where it was violated.
Importantly, this lint is NOT turned on for flutter/packages/test, because those changes are happening in another PR: #84478
This adds iOS key map generation that uses std::maps. It uses std::maps because on iOS if we use NSDictionaries, then when XCode loads the dylib, the initialization of those status NSDictionaries hasn't yet occurred, and it crashes the app. std::maps have a well-defined static behavior, and are correctly initialized.
I also made the naming of variables, fields, etc. consistent for macOS. We variously had macosFoo, macOSFoo, and macOsFoo. I eliminated macOsFoo and macosFoo, since the rest of the repo uses macOSFoo for lowerCamelCase names (with only a few exceptions). I used iOSFoo for iOS.
