fix(deps): pin fflate via @arethetypeswrong/core override

[overbalance]

Which problem is this PR solving?

@arethetypeswrong/core pulls in a newer transitive fflate version that's incompatible with our setup. Pinning it via npm overrides keeps fflate at a known-good version without waiting on an upstream release.

Short description of the changes

• Add overrides.@arethetypeswrong/core.fflate = 0.8.2 in root package.json
• Refreshed package-lock.json to apply the override

Type of change

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• This change requires a documentation update

How Has This Been Tested?

• npm install resolves cleanly
• npm run check passes (pre-commit hook)

Checklist:

• Followed the style guidelines of this project
• Unit tests have been added
• Documentation has been updated