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* Auto generate mapping files with command `java -jar grasscutter.jar -gachamap`

* Static file provider
  * For gacha record webpage
  * All static files should be stored at `GRASSCUTTER_RESOURCE/gcstatic/`
  * Can benefit other subsystem in future when webpages involved

This reverts commit 215ee2a3.

This fixes potential output issues for non-Latin scripts when exporting the handbook by changing the filename in the code.