refactor: migrate server state management to Tanstack Query

[allison-truhlar]

This pull request introduces several improvements and refactors to the frontend codebase, focusing on migrating data fetching and state management to React/Tanstack Query.

React Query Integration:

• Added @tanstack/react-query, @tanstack/react-query-devtools, and @tanstack/eslint-plugin-query dependencies.
• Replaced usage of useEffects for data fetching with the queries.
• Updated frontend unit test utilities to wrap components in a QueryClientProvider.

Miscellaneous:

• Fixed Playwright tests by forcing them to run in parallel, have each test create a unique folder to generate test files in, and clearing the shared database at the end of each test.
• Added Playwright test report directory to .prettierignore to avoid formatting issues with generated reports.
• Fixed error on push: 'Can't find lefthook in PATH' by explicitly setting the lefthook location and command in lefthook.yml. This error resulted from the refactor that moved the frontend code, where lefthook is installed via npm.
• Added a frontend directory CLAUDE.md file to aid Claude Code in following the development patterns in this directory across collaborators.

Note: this PR now has several other PRs merged into it:
#236
#237
#238
#239