Feat: Prevent too large data from transfer unless requested

Context: Some Wolfram expressions may, perhaps surprisingly, return large data - f.ex. VideoTrim and =. This makes evaluation slow, as we need to transfer and parse all this possibly undesirable data, and may lead up to OutOfMemory exception. Action: When the result seems to be too large, return instead `:wolframite/large-data`. Only allow returning results bigger than the threshold when explicitly requested via the `flags/allow-large-data` flag. Notice this can only be done on Wolfram side, so we wrap expressions with a tiny piece of code (loaded in at startup) that we then use. Also included: * Fix: Ensure that when custom opts provided, we still respect the defaults (essential, as some config vals are there). * Refactoring: Add internal-constants ns for better readability. More details: * Add `convert/wrapping-convert` as the top-level convert call, similarly with `parse/unwrapping-parse` * Add `proto/failed?` to recognize the `$Failed` symbol * Add `internal-constants` ns for some of the new stuff * Replaced `proto/number?` with `proto/number-type?`