chore(frontend): enforce no-explicit-any and tidy JSDoc (#656)

- Flip @typescript-eslint/no-explicit-any from 'off' to 'error' to lock
  in the existing zero-`any` state; no violations surfaced.
- Remove the stale .eslintrc.cjs entry from the flat-config ignores.
- Add /** JSDoc to the Checkbox, Input, Spinner, EmptyState, and
  DateHierarchyBar primitives for doc consistency.

Verified: pnpm lint:js, pnpm lint:css, pnpm typecheck all pass.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

Author: martin-castro-laminr-ai

frontend/eslint.config.mjs

@@ -21,7 +21,6 @@ export default tseslint.config(
       '**/node_modules/**',
       '**/*.config.{js,cjs,mjs,ts}',
       'vitest.setup.ts',
-      '.eslintrc.cjs',
     ],
   },
   js.configs.recommended,
@@ -34,10 +33,11 @@ export default tseslint.config(
     plugins: { 'react-hooks': reactHooks },
     rules: {
       ...reactHooks.configs.recommended.rules,
-      // `Any` is used deliberately at wire boundaries (parsed JSON,
-      // Django-shaped signatures) — mirrors the Python side keeping
-      // `Any`. Tightening the tractable cases is tracked separately.
-      '@typescript-eslint/no-explicit-any': 'off',
+      // The codebase carries zero `any` today; lock that in (#656). A
+      // genuine wire boundary that needs `any` should add a narrowly
+      // scoped per-line `eslint-disable-next-line` with a reason rather
+      // than reopening the rule globally.
+      '@typescript-eslint/no-explicit-any': 'error',
       // Align with tsconfig's `noUnusedParameters` underscore convention.
       '@typescript-eslint/no-unused-vars': [
         'error',

frontend/packages/list/src/DateHierarchyBar.tsx

@@ -20,10 +20,13 @@ export interface DateHierarchyBarProps {
   onNavigate: (path: { year?: number | null; month?: number | null; day?: number | null }) => void;
 }
 
-// date_hierarchy drill-down bar (#304 — Django changelist parity). Reads
-// `active` for the current drill path (breadcrumb, each crumb navigates
-// up) and `buckets` for the next level's options (drill down). The
-// backend caps the level by the field; clicking wires ?year/?month/?day.
+/**
+ * `date_hierarchy` drill-down bar (#304 — Django changelist parity).
+ * Reads `dh.active` for the current drill path (a breadcrumb whose crumbs
+ * navigate up) and `dh.buckets` for the next level's options (drill down).
+ * The backend caps the level by the field; clicking calls `onNavigate`
+ * with the chosen `?year`/`?month`/`?day`.
+ */
 export function DateHierarchyBar({ dh, onNavigate }: DateHierarchyBarProps) {
   const { active, buckets } = dh;
   const level: 'year' | 'month' | 'day' | 'done' =

frontend/packages/ui/src/Checkbox.tsx

@@ -12,6 +12,12 @@ import type { InputHTMLAttributes } from 'react';
 
 export type CheckboxProps = Omit<InputHTMLAttributes<HTMLInputElement>, 'type'>;
 
+/**
+ * Styled checkbox primitive: an `appearance-none` box that matches the
+ * themed text inputs (border + transparent surface) with a primary fill
+ * and inline-SVG tick when checked. Accepts all native checkbox input
+ * attributes except `type`.
+ */
 export function Checkbox({ className = '', ...rest }: CheckboxProps) {
   return (
     <span className="relative inline-flex h-4 w-4 shrink-0 align-middle">

frontend/packages/ui/src/EmptyState.tsx

@@ -6,6 +6,11 @@ export interface EmptyStateProps {
   action?: ReactNode;
 }
 
+/**
+ * Centered placeholder for empty collections: a required `title`, an
+ * optional `description`, and an optional `action` node (e.g. an "Add"
+ * button) rendered below.
+ */
 export function EmptyState({ title, description, action }: EmptyStateProps) {
   return (
     <div className="flex flex-col items-center justify-center text-center py-12 px-4">

frontend/packages/ui/src/Input.tsx

@@ -6,6 +6,11 @@ export interface InputProps extends InputHTMLAttributes<HTMLInputElement> {
   error?: ReactNode;
 }
 
+/**
+ * Text input primitive with an optional label, help text, and error
+ * message. Generates a stable-per-render `id` when none is supplied so the
+ * label's `htmlFor` always resolves. Forwards all native input attributes.
+ */
 export function Input({ label, helpText, error, id, className = '', ...rest }: InputProps) {
   const inputId = id ?? `dar-input-${Math.random().toString(36).slice(2, 8)}`;
   return (

frontend/packages/ui/src/Spinner.tsx

@@ -9,6 +9,11 @@ const SIZE_CLASSES: Record<NonNullable<SpinnerProps['size']>, string> = {
   lg: 'h-10 w-10',
 };
 
+/**
+ * Animated loading spinner with an `aria-live` status region. `size`
+ * selects one of three preset dimensions (default `md`); an optional
+ * `label` renders beside the spinner and is announced to assistive tech.
+ */
 export function Spinner({ size = 'md', label }: SpinnerProps) {
   return (
     <span role="status" aria-live="polite" className="inline-flex items-center gap-2 text-gray-500">