test: resolve TS errors in test files

[metonym]

The updates tsconfig.json to:

• omit specific extensions in tsconfig.json#include to resolve type error for ".svelte" files and remove "unused @ts-expect-error directive" warnings
• remove useless tick usage since @testing-library/user-event is awaited
• enable resolveJsonModules to resolve type error when importing package.json
• remove unused

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[render[bot]]

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