Epic: Fix linting errors across VRMS codebase

### Overview
Now that VRMS enforces linting in pull requests, we need to address and resolve all existing linting errors across the codebase. This epic will track the investigation and resolution of lint violations across individual files, ensuring PRs can pass checks and improving code quality and consistency.

_- Note - VRMS Team members will be fixing ESLint errors in the files they are editing while working on other github issues. We will not be resolving ESLint errors file-by-file._

### Action Items
- [ ] https://github.com/hackforla/VRMS/issues/1967
- [ ] #1969
- [ ] https://github.com/hackforla/VRMS/issues/1968
- [ ] Run the script, copy its output and update the linting error file list below each week.
- **Files containing linting errors** (updated on **2025-06-18**):
- /backend/app.js
- /backend/config/auth.config.js
- /backend/config/auth.config.test.js
- /backend/controllers/email.controller.test.js
- /backend/controllers/event.controller.js
- /backend/controllers/event.controller.test.js
- /backend/controllers/project.controller.js
- /backend/controllers/project.controller.test.js
- /backend/controllers/recurringEvent.controller.js
- /backend/controllers/user.controller.js
- /backend/controllers/user.controller.test.js
- /backend/jest.setup.js
- /backend/middleware/auth.middleware.js
- /backend/middleware/errorhandler.middleware.js
- /backend/middleware/token.middleware.js
- /backend/models/user.model.js
- /backend/routers/auth.router.js
- /backend/routers/checkIns.router.js
- /backend/routers/checkIns.router.test.js
- /backend/routers/checkUser.router.test.js
- /backend/routers/grantpermission.router.js
- /backend/routers/projectTeamMembers.router.js
- /backend/routers/questions.router.js
- /backend/routers/slack.router.js
- /backend/routers/users.router.test.js
- /backend/setup-test.js
- /backend/test/old-tests/auth.router.test.js
- /backend/test/old-tests/events.router.test.js
- /backend/test/old-tests/projects.router.test.js
- /backend/test/old-tests/users.router.test.js
- /backend/workers/createRecurringEvents.test.js
- /backend/workers/lib/generateEventData.js
- /backend/workers/openCheckins.js
- /backend/workers/slackbot.js
- /client/build/assets/index-a2c2d1af.js
- /client/src/App.jsx
- /client/src/api/UserApiService.js
- /client/src/common/tabs/index.jsx
- /client/src/common/tabs/tab.jsx
- /client/src/components/ChangesModal.jsx
- /client/src/components/DashboardUsers.jsx
- /client/src/components/ErrorContainer.jsx
- /client/src/components/Footer.jsx
- /client/src/components/Form.jsx
- /client/src/components/Header.jsx
- /client/src/components/Leaderboard.jsx
- /client/src/components/Leaderboard.test.jsx
- /client/src/components/Navbar.jsx
- /client/src/components/ProjectForm.jsx
- /client/src/components/ReadyEvents.jsx
- /client/src/components/admin/dashboard/index.jsx
- /client/src/components/admin/donutChart.jsx
- /client/src/components/admin/donutChartContainer.jsx
- /client/src/components/admin/donutChartLoading.jsx
- /client/src/components/admin/eventOverview.jsx
- /client/src/components/admin/reports/index.jsx
- /client/src/components/auth/Auth.jsx
- /client/src/components/auth/HandleAuth.jsx
- /client/src/components/dashboard/AddTeamMember.jsx
- /client/src/components/dashboard/AttendeeTable.jsx
- /client/src/components/dashboard/AttendeeTableRow.jsx
- /client/src/components/dashboard/DashboardButton.jsx
- /client/src/components/dashboard/ProjectInfo.jsx
- /client/src/components/dashboard/RosterTable.jsx
- /client/src/components/dashboard/RosterTableRow.jsx
- /client/src/components/manageProjects/addProject.jsx
- /client/src/components/manageProjects/createNewEvent.jsx
- /client/src/components/manageProjects/editMeetingTimes.jsx
- /client/src/components/manageProjects/editProject.jsx
- /client/src/components/manageProjects/editableField.jsx
- /client/src/components/manageProjects/editableMeeting.jsx
- /client/src/components/manageProjects/eventForm.jsx
- /client/src/components/manageProjects/selectProject.jsx
- /client/src/components/manageProjects/utilities/readableEvent.js
- /client/src/components/parts/boxes/TitledBox.jsx
- /client/src/components/parts/form/ValidatedTextField.jsx
- /client/src/components/presentational/CheckInButtons.jsx
- /client/src/components/presentational/CreateNewProfileButton.jsx
- /client/src/components/presentational/DashboardReport.jsx
- /client/src/components/presentational/newUserForm.jsx
- /client/src/components/presentational/profile/ProfileOption.jsx
- /client/src/components/presentational/profile/UserEvents.jsx
- /client/src/components/presentational/profile/UserTable.jsx
- /client/src/components/presentational/profile/UserTeams.jsx
- /client/src/components/presentational/projectDashboardContainer.jsx
- /client/src/components/presentational/returnUserForm.jsx
- /client/src/components/presentational/upcomingEvent.jsx
- /client/src/components/user-admin/AddNewProject.jsx
- /client/src/components/user-admin/EditUsers.jsx
- /client/src/components/user-admin/UserManagement.jsx
- /client/src/components/user-admin/UserPermissionSearch.jsx
- /client/src/context/authContext.jsx
- /client/src/context/snackbarContext.jsx
- /client/src/context/userContext.jsx
- /client/src/hooks/withAuth.jsx
- /client/src/index.jsx
- /client/src/pages/CheckInForm.jsx
- /client/src/pages/EmailSent.jsx
- /client/src/pages/Event.jsx
- /client/src/pages/Events.jsx
- /client/src/pages/HealthCheck.jsx
- /client/src/pages/Home.jsx
- /client/src/pages/ManageProjects.jsx
- /client/src/pages/NewUser.jsx
- /client/src/pages/ProjectLeaderDashboard.jsx
- /client/src/pages/ProjectList.jsx
- /client/src/pages/ReturningUser.jsx
- /client/src/pages/SecretPassword.jsx
- /client/src/pages/Success.jsx
- /client/src/pages/UserAdmin.jsx
- /client/src/pages/UserDashboard.jsx
- /client/src/pages/UserPermission.jsx
- /client/src/pages/UserPermissionSearch.jsx
- /client/src/pages/UserProfile.jsx
- /client/src/pages/UserWelcome.jsx
- /client/src/pages/Users.jsx
- /client/src/utils/authUtils.js
- /cypress/integration/admin_login.js
- /cypress/integration/home_page.js
- /cypress/plugins/index.js
- /github-actions/pr-instructions/create-instruction.js
- [ ] Close this epic once the list of files containing linting errors above is empty.

### Resources/Instructions
- Run `yarn lint` to see current issues.
- Consider using `eslint --fix` or tools like [jscodeshift](https://github.com/facebook/jscodeshift) for bulk code transformations.
- Refer to `.eslintrc.js` for specific rule definitions.