Fixes#9551.
Removes various .keyboard_info files from test fixtures and also removes
generation of .keyboard_info source files from kmconvert, alongside now-
redundant tests (cvt.dpr).
This starts the refactor of the .kmn compiler interfaces for WASM,
moving more file writes into typescript and out of the compiler. Adds a
cleaner binding and structures for passing compile metadata back to
typescript for additional build steps (e.g. kvk, js builds).
Will rebase the Typescript-based KMW compiler onto this so it can start
to benefit from the refactoring.
* Fixes a minor issue with loading a .kvks file with an empty flags set.
* Adds a writeFileSync method to the compiler callback interfaces.
* Adds an e2e compiler test to verify that .kmx and .kvk are both
correctly compiled.
Relates to #3620.
Allows keyboard developers to add a Caps Lock layer (called 'caps'),
which will be accessible through double-tap of Shift key, in an upcoming
PR.
Also adds test keyboards to exercise the functionality when it is
available.
