feat(tests): enhance test coverage and error handling across various components

- Added a test case in CrowdSecConfig to show improved error message when preset is not cached.
- Introduced a new test suite for the Dashboard component, verifying counts and health status.
- Updated SMTPSettings tests to utilize a shared render function and added tests for backend validation errors.
- Modified Security.audit tests to improve input handling and removed redundant export failure test.
- Refactored Security tests to remove export functionality and ensure correct rendering of components.
- Enhanced UsersPage tests with new scenarios for updating user permissions and manual invite link flow.
- Created a new utility for rendering components with a QueryClient and MemoryRouter for better test isolation.
- Updated go-test-coverage script to improve error handling and coverage reporting.

docs/plans/frontend_coverage_boost.md

@@ -0,0 +1,52 @@
+# Frontend Coverage Boost Plan (>=85%)
+
+Current (QA): statements 84.54%, branches 75.85%, functions 78.97%.
+Goal: reach >=85% with the smallest number of high-yield tests.
+
+## Targeted Tests (minimal set with maximum lift)
+- **API units (fast, high gap)**
+  - [src/api/notifications.ts](frontend/src/api/notifications.ts): cover payload branches in `previewProvider` (with/without `data`) and `previewExternalTemplate` (id vs inline template vs both), plus happy-path CRUD wrappers to verify endpoint URLs.
+  - [src/api/logs.ts](frontend/src/api/logs.ts): assert `getLogContent` query param building (search/host/status/level/sort), `downloadLog` sets `window.location.href`, and `connectLiveLogs` callbacks for `onOpen`, `onMessage` (valid JSON), parse error branch, `onError`, and `onClose` (closing when readyState OPEN/CONNECTING).
+  - [src/api/users.ts](frontend/src/api/users.ts): cover invite, permissions update, validate/accept invite paths; assert returned shapes and URL composition (e.g., `/users/${id}/permissions`).
+
+- **Component tests (few, branch-heavy)**
+  - [src/pages/SMTPSettings.tsx](frontend/src/pages/SMTPSettings.tsx): component test with React Testing Library (RTL).
+    - Ensure initial render waits for query then hydrates host/port/encryption (flaky area); verify loading spinner disappears.
+    - Save success vs error toast branches; `Test Connection` success/error; `Send Test Email` success clears input and error path shows toast.
+    - Button disables: test connection disabled when `host` or `fromAddress` empty; send test disabled when `testEmail` empty.
+  - [src/components/LiveLogViewer.tsx](frontend/src/components/LiveLogViewer.tsx): component test with mocked `WebSocket` and `connectLiveLogs`.
+    - Verify pause/resume toggles, log trimming to `maxLogs`, filter by text/level, parse-error branch (bad JSON), and disconnect cleanup invokes returned close fn.
+  - [src/pages/UsersPage.tsx](frontend/src/pages/UsersPage.tsx): component test.
+    - Invite modal success when `email_sent` false shows manual link copy branch; toggle permission mode text for allow_all vs deny_all; checkbox host toggle logic.
+    - Permissions modal seeds state from selected user and saves via `updateUserPermissions` mutation.
+    - Delete confirm branch (stub `confirm`), enabled Switch disabled for admins, enabled toggles for non-admin users.
+
+- **Security & CrowdSec flows**
+  - [src/pages/CrowdSecConfig.tsx](frontend/src/pages/CrowdSecConfig.tsx): component test (can mock queries/mutations).
+    - Cover hub unavailable (503) -> `preset-hub-unavailable`, cached preview fallback via `getCrowdsecPresetCache`, validation error (400) -> `preset-validation-error`, and apply fallback when backend returns 501 to hit local apply path and `preset-apply-info` rendering.
+    - Import flow with file set + disabled state; mode toggle (`crowdsec-mode-toggle`) updates via `updateSetting`; ensure decisions table renders "No banned IPs" vs list.
+  - [src/pages/Security.tsx](frontend/src/pages/Security.tsx): component test.
+    - Banner when `cerberus.enabled` is false; toggles `toggle-crowdsec`/`toggle-acl`/`toggle-waf`/`toggle-rate-limit` call mutations and optimistic cache rollback on error.
+    - LiveLogViewer renders only when Cerberus enabled; whitelist input saves via `useUpdateSecurityConfig` and break-glass button triggers mutation.
+
+- **Shell/UI overview**
+  - [src/pages/Dashboard.tsx](frontend/src/pages/Dashboard.tsx): component test to cover health states (ok, error, undefined) and counts computed from hooks.
+  - [src/components/Layout.tsx](frontend/src/components/Layout.tsx): component test.
+    - Feature-flag filtering (hide Uptime/Cerberus when flags false), sidebar collapse persistence (localStorage), mobile toggle (`data-testid="mobile-menu-toggle"`), nested menu expand/collapse, logout button click, and version/git commit rendering.
+
+- **Missing/low names from QA list**
+  - `Summary.tsx`, `FeatureFlagProvider.tsx`, `useFeatureFlags.ts`, `LiveLogViewerRow.tsx`: confirm current paths (may have been renamed). Add light RTL/unit tests mirroring above patterns if still present (e.g., summary widget rendering counts, provider supplying default flags).
+
+## SMTPSettings Deflake Strategy
+- Wait for data: use `await screen.findByText('Email (SMTP) Settings')` and `await waitFor(() => expect(hostInput).toHaveValue('...'))` after mocking `getSMTPConfig` to resolve once.
+- Avoid racing mutations: wrap `vi.useFakeTimers()` only if timers are used; otherwise keep real timers and `await act(async () => ...)` on mutations.
+- Reset query cache per test (`queryClient.clear()` or `QueryClientProvider` fresh instance) and isolate toast spies.
+- Prefer role/label queries (`getByLabelText('SMTP Host')`) over brittle text selectors; ensure `toast` mocks are flushed before assertions.
+
+## Ordered Phases (minimal steps to >=85%)
+- Phase 1 (API unit bursts) — expected +0.30 to statements: notifications.ts, logs.ts, users.ts.
+- Phase 2 (UI quick wins) — expected +0.50: SMTPSettings, LiveLogViewer, UsersPage.
+- Phase 3 (Security shell) — expected +0.40: CrowdSecConfig, Security page.
+- Phase 4 (Shell polish) — expected +0.20: Dashboard, Layout, any remaining Summary/feature-flag provider files if present.
+
+Total projected lift: ~+1.4% (buffered) with 8–10 focused tests. Stop after Phase 3 if coverage already surpasses 85%; Phase 4 only if buffer needed.