fix: all lint errors, test + lint pre-commit passing

Frontend:
- Split nodeTypes/edgeTypes into separate .ts files (react-refresh)
- Remove setState-in-effect in NodeModal (key prop reset)
- Fix handleSave accessed before declaration (useRef pattern)
- Exclude src/components/ui/** from eslint (shadcn generated)
- Use defineConfig from vitest/config for test type support

Backend:
- ruff --fix: sort imports, datetime.UTC alias
- Raise line-length to 120, ignore E501 in tests
- Break long update_node/update_edge signatures
- pyproject.toml: per-file-ignores for tests

frontend/src/stores/__tests__/authStore.test.ts

@@ -0,0 +1,29 @@
+import { describe, it, expect, beforeEach } from 'vitest'
+import { useAuthStore } from '@/stores/authStore'
+
+describe('authStore', () => {
+  beforeEach(() => {
+    useAuthStore.setState({ token: null, isAuthenticated: false })
+  })
+
+  it('starts unauthenticated', () => {
+    const { token, isAuthenticated } = useAuthStore.getState()
+    expect(token).toBeNull()
+    expect(isAuthenticated).toBe(false)
+  })
+
+  it('login sets token and isAuthenticated', () => {
+    useAuthStore.getState().login('my-jwt-token')
+    const { token, isAuthenticated } = useAuthStore.getState()
+    expect(token).toBe('my-jwt-token')
+    expect(isAuthenticated).toBe(true)
+  })
+
+  it('logout clears token and isAuthenticated', () => {
+    useAuthStore.getState().login('my-jwt-token')
+    useAuthStore.getState().logout()
+    const { token, isAuthenticated } = useAuthStore.getState()
+    expect(token).toBeNull()
+    expect(isAuthenticated).toBe(false)
+  })
+})