feat: Export createFromMapFiles SourceMapper utility

[VladimirMilenko]

This functionality is needed when you know exact source map location and other source maps can fail.
Our use case:
We know exactly location of server.map.js file, however, some of client maps have references to WASM code and thus SourceMap is unable to parse them.
Being unable to parse at least one of sourcemaps, error is thrown and sourcemaps are no longer available.

This functionality will allow you to pass path to specific sourcemap and avoid issue described above.

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