fix(developer): move osk.ts from developer-utils to kmc-kmn

Fixes #10872. Modifies #10845.

developer-utils is also used by server. Because osk.ts depends on
common-types, this introduced a transitive dependency for
developer-utils. Packaging server for deployment as part of Keyman
Developer is fragile and we need to hand-code our internal dependencies,
as npm bundling struggles with in-repo dependencies. So we need to avoid
introducing extra dependencies into developer-utils at this time.

It turns out that osk.ts is used by kmc-kmn and kmc-analyze. kmc-analyze
already has a dependency on kmc-kmn, so it makes sense to put it there.