E2E Test Selection:
This PR is a pure refactoring of E2E test infrastructure - moving selector files from e2e/selectors/ to tests/selectors/ and utility files from e2e/utils/ to tests/helpers/, then updating all import paths accordingly. No actual test logic or selector values are changed.

The changes affect multiple test areas:

1. SmokeMultiChainAPI: Directly affected - multichain test specs (wallet-createSession, wallet-getSession, wallet-revokeSession, wallet-sessionChanged) have updated imports for MultichainUtilities and MultichainTestDapp selectors
2. FlaskBuildTests: Directly affected - test-snap-background-events.spec.ts has updated import for TestSnaps.selectors
3. SmokeNetworkExpansion: Affected via SolanaTestDApp.ts import path changes
4. SmokeTrade: Affected via QuoteView.ts, SlippageModal.ts, and swaps/OnBoarding.ts import path changes
5. SmokeRamps: Affected via BuyGetStartedView.ts, SelectPaymentMethodView.ts, SelectRegionView.ts, SellGetStartedView.ts import path changes
6. SmokeIdentity: Affected via BackupAndSyncView.ts import path changes
7. SmokeConfirmations: Affected via RedesignedSendView.ts and SendActionBottomSheet.ts import path changes (send flows)

The wdio/ changes are for a separate test framework (WebDriverIO/Appwright) and don't require Detox tags.

Since this is infrastructure refactoring that could break tests if import paths are incorrect, running the affected test suites validates the changes work correctly. The risk is medium because while the changes are straightforward path updates, any typo or incorrect path would cause test failures.

Performance Test Selection:
This PR is purely a test infrastructure refactoring that moves selector files and updates import paths. No application code, UI components, data loading logic, or performance-critical paths are modified. The changes only affect E2E test file organization and have no impact on app performance.