Fix local resource URLs with hashes

[maxrross]

Fixes #4015.

Summary

• Escape local Electron file URLs so # and ? in resource paths are treated as path characters instead of URL fragments/query markers.
• Decode escaped file URLs when turning resource URLs back into local paths.
• Add regression coverage for hashed resource paths and decoded local paths.

Tests

• npm --prefix newIDE/app test -- --runTestsByPath src/ResourcesLoader/index.spec.js src/ResourcesList/ResourceUtils.spec.js --watchAll=false