fix: remove any types, dead code, unused exports; add comprehensive tests

- Fix handleRotate bug ignoring Result from rotateSealedSecret()
- Fix dead code branch in useControllerHealth
- Replace all `any` types with `unknown` + type guards
- Delete unused functions/exports (452 lines removed)
- Add 18 new test files covering all hooks, libs, and components
- 233 tests passing, zero tsc errors, zero lint issues

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

src/components/SettingsPage.test.tsx

@@ -0,0 +1,144 @@
+/**
+ * Unit tests for SettingsPage component
+ */
+
+import { fireEvent, render, screen } from '@testing-library/react';
+import React from 'react';
+import { beforeEach, describe, expect, it, vi } from 'vitest';
+
+// Mock notistack
+const mockEnqueueSnackbar = vi.fn();
+vi.mock('notistack', () => ({
+  useSnackbar: () => ({ enqueueSnackbar: mockEnqueueSnackbar }),
+}));
+
+// Mock controller
+vi.mock('../lib/controller', () => ({
+  getPluginConfig: vi.fn().mockReturnValue({
+    controllerName: 'sealed-secrets-controller',
+    controllerNamespace: 'kube-system',
+    controllerPort: 8080,
+  }),
+  savePluginConfig: vi.fn(),
+}));
+
+// Mock sub-components
+vi.mock('./ControllerStatus', () => ({
+  ControllerStatus: () => <div data-testid="controller-status">Status</div>,
+}));
+
+vi.mock('./VersionWarning', () => ({
+  VersionWarning: () => <div data-testid="version-warning">Version</div>,
+}));
+
+vi.mock('@kinvolk/headlamp-plugin/lib/CommonComponents', () => ({
+  SectionBox: ({ title, children }: { title: string; children: React.ReactNode }) => (
+    <div data-testid="section-box">
+      <h2>{title}</h2>
+      {children}
+    </div>
+  ),
+}));
+
+import { savePluginConfig } from '../lib/controller';
+import { SettingsPage } from './SettingsPage';
+
+const mockSave = vi.mocked(savePluginConfig);
+
+describe('SettingsPage', () => {
+  beforeEach(() => {
+    vi.clearAllMocks();
+  });
+
+  it('should render settings form with default values', () => {
+    render(<SettingsPage />);
+
+    expect(screen.getByText('Sealed Secrets Plugin Settings')).toBeDefined();
+    expect(screen.getByDisplayValue('sealed-secrets-controller')).toBeDefined();
+    expect(screen.getByDisplayValue('kube-system')).toBeDefined();
+    expect(screen.getByDisplayValue('8080')).toBeDefined();
+  });
+
+  it('should render ControllerStatus and VersionWarning', () => {
+    render(<SettingsPage />);
+
+    expect(screen.getByTestId('controller-status')).toBeDefined();
+    expect(screen.getByTestId('version-warning')).toBeDefined();
+  });
+
+  it('should save config on Save button click', () => {
+    render(<SettingsPage />);
+
+    fireEvent.click(screen.getByText('Save Settings'));
+
+    expect(mockSave).toHaveBeenCalledWith({
+      controllerName: 'sealed-secrets-controller',
+      controllerNamespace: 'kube-system',
+      controllerPort: 8080,
+    });
+    expect(mockEnqueueSnackbar).toHaveBeenCalledWith('Settings saved successfully', {
+      variant: 'success',
+    });
+  });
+
+  it('should reset to defaults on Reset button click', () => {
+    render(<SettingsPage />);
+
+    // Change a value first
+    const nameInput = screen.getByDisplayValue('sealed-secrets-controller');
+    fireEvent.change(nameInput, { target: { value: 'custom-name' } });
+    expect(screen.getByDisplayValue('custom-name')).toBeDefined();
+
+    // Reset
+    fireEvent.click(screen.getByText('Reset to Defaults'));
+
+    expect(screen.getByDisplayValue('sealed-secrets-controller')).toBeDefined();
+    expect(screen.getByDisplayValue('kube-system')).toBeDefined();
+    expect(screen.getByDisplayValue('8080')).toBeDefined();
+  });
+
+  it('should call onDataChange when form fields change', () => {
+    const onDataChange = vi.fn();
+    render(<SettingsPage onDataChange={onDataChange} />);
+
+    const nameInput = screen.getByDisplayValue('sealed-secrets-controller');
+    fireEvent.change(nameInput, { target: { value: 'new-controller' } });
+
+    expect(onDataChange).toHaveBeenCalledWith(
+      expect.objectContaining({
+        controllerName: 'new-controller',
+      })
+    );
+  });
+
+  it('should call onDataChange on save', () => {
+    const onDataChange = vi.fn();
+    render(<SettingsPage onDataChange={onDataChange} />);
+
+    fireEvent.click(screen.getByText('Save Settings'));
+
+    expect(onDataChange).toHaveBeenCalled();
+  });
+
+  it('should use data props for initial values when provided', () => {
+    render(
+      <SettingsPage
+        data={{
+          controllerName: 'from-props',
+          controllerNamespace: 'custom-ns',
+          controllerPort: 9090,
+        }}
+      />
+    );
+
+    expect(screen.getByDisplayValue('from-props')).toBeDefined();
+    expect(screen.getByDisplayValue('custom-ns')).toBeDefined();
+    expect(screen.getByDisplayValue('9090')).toBeDefined();
+  });
+
+  it('should show default values info section', () => {
+    render(<SettingsPage />);
+
+    expect(screen.getByText('Default Values')).toBeDefined();
+  });
+});