React Hooks + Compiler

[dtemkin1]

Works on fixing React Rule of Hooks ESLint issues and activating automatic memoization using the React Compiler. Also finding a few bugs along the way but... anyways.

Resolves #116

[Copilot]

Pull request overview

This pull request implements React Compiler for automatic memoization and fixes React Hooks ESLint violations in the Hydrant codebase. The changes enable the React Compiler babel plugin and activate the react-hooks ESLint rules that were previously commented out.

Changes:

• Adds React Compiler via babel-plugin-react-compiler and vite-plugin-babel configuration
• Enables React Hooks ESLint rules (reactHooks.configs.flat.recommended)
• Refactors components to comply with Rules of Hooks by fixing dependency arrays, converting useEffect to render-time state updates, and extracting components
• Converts setter properties to explicit setter methods in State, Sections, and ClassSections classes for better React Compiler compatibility

Reviewed changes

Copilot reviewed 15 out of 16 changed files in this pull request and generated 2 comments.

Show a summary per file

File	Description
vite.config.ts	Adds vite-plugin-babel configuration with babel-plugin-react-compiler for automatic memoization
eslint.config.js	Enables react-hooks ESLint rules that were previously commented out
package.json	Adds babel-plugin-react-compiler and vite-plugin-babel dev dependencies
package-lock.json	Updates lockfile with new babel and vite plugin dependencies
src/lib/state.ts	Converts showBanner setter to setShowBanner method and adds setFitsScheduleCallback method
src/lib/class.ts	Adds setRoomOverride method and removes declare keyword from kind property
src/lib/activity.ts	Adds setRoomOverride method to Sections class
src/lib/hydrant.ts	Adds eslint-disable for exhaustive-deps to suppress stable function warnings
src/emotion/emotion-client.tsx	Adds eslint-disable for intentional cache mutation
src/routes/overrides.($prefillId).tsx	Fixes useCallback dependency array by removing module-level overrides variable
src/components/ScheduleSwitcher.tsx	Replaces useEffect with render-time state derivation pattern for syncing props to state
src/components/PEClassTable.tsx	Removes unused state dependency from useMemo and updates to use setFitsScheduleCallback method
src/components/ClassTable.tsx	Updates to use setFitsScheduleCallback method
src/components/Header.tsx	Adds "use no memo" directive to opt-out PreferencesDialog from React Compiler
src/components/Banner.tsx	Updates to use setShowBanner method instead of property setter
src/components/ActivityButtons.tsx	Adds "use no memo" directives, extracts RenderCheckboxes component, adds key prop for controlled remounting, and removes useLayoutEffect

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