feat(es/minifier): Make minifier parallel

[kdy1]

swc_ecma_minifier:

• Introduce bundle mode, which can be used to parallelize processing of bundled files.
• Add a function analyzer that checks if the function references something from the outer scope.
• Split out parellsizable passes.
• Split optimzer into pure / non-pure.
• Run pure optimizations in parallel.

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Closes #1987.