admin: semantic HTML pass — checkbox fieldset, landmarks, dl/dt, autocomplete, inline styles

checkbox-list.php partial:
- Replace outer <div>/<label> with <div>/<span class="admin-row-label"> + inner
  <fieldset class="admin-checkbox-group"><legend class="sr-only"> to satisfy
  WCAG 1.3.1 (group label for multi-checkbox rows without duplicating visible text)
- Replace <div class="admin-checkbox-list"> with <ul>; each checkbox wrapped in <li>

admin.css:
- Drop .admin-checkbox-list; add .admin-body fieldset.admin-checkbox-group rules
  (border/padding reset so it doesn't inherit jury-fieldset box styling)
- Extend form-row label rule to span.admin-row-label
- .admin-inline-form + .admin-inline-form { margin-top:.35rem } replaces inline style
- .admin-input--inline / .admin-select--inline get width:160px (was inline style)
- .admin-tags-count + table th sizing via :has() replaces th inline styles

login.php: wrap content in <main id="main-content"> (missing landmark)

account.php:
- <div class="admin-account-status"> → <dl>; __label <span> → <dt>
- <div class="admin-danger-zone__description"> → <p>

index.php: <div class="admin-maintenance-bar"> → <aside role="status" aria-label="Statut du site">

add.php / edit.php: autocomplete="name" on author field, autocomplete="email" on
contact field (WCAG 1.3.5 / input purpose)

tags.php: all inline style= attributes removed (width, text-align, margin-top,
display:inline); all moved to CSS classes

todo/04-accessibility.md

@@ -6,13 +6,13 @@
 
 ## 1.3.1 Info and relationships
 
-- [ ] **Admin form rows: multi-input rows (languages, formats)** — `<label class="admin-label">` without `for` labels a group of checkboxes; replace with `<fieldset>/<legend>`
+- [x] **Admin form rows: multi-input rows (languages, formats)** — `checkbox-list.php` partial now wraps checkboxes in `<fieldset class="admin-checkbox-group">` with a `<legend class="sr-only">` for AT grouping
 
 - [ ] **Status badges in `admin/index.php` convey state by colour alone** — add visible non-colour distinction (prefix icon with `aria-hidden="true"`) and `aria-label="Statut : Publié"` on badge `<span>`
 
 ## 1.3.4 / 1.3.5 Orientation & Input purpose
 
-- [ ] **No `autocomplete` attributes on personal data fields** — `add.php`/`edit.php`: add `autocomplete="name"` on author fields, `autocomplete="email"` on mail fields
+- [x] **No `autocomplete` attributes on personal data fields** — `add.php`/`edit.php`: `autocomplete="name"` on author fields, `autocomplete="email"` on mail fields (via `$attrs` in `text-field.php`)
 
 ## 1.4.1 Use of colour
 
@@ -57,7 +57,8 @@
 
 ## 3.3.1 Error identification
 
-- [ ] **`add.php`/`formulaire.php` validation errors** — add `role="alert"` to error div; add `autofocus` to first invalid field when re-rendering form with session error data
+- [x] **`add.php`/`edit.php` validation errors** — `flash-messages.php` already emits `<p role="alert" data-type="error">` for errors and `<p role="status">` for success
+- [ ] **`add.php`/`edit.php` `autofocus` on first invalid field** — requires controller to pass back which field failed; deferred (larger refactor)
 
 ## 3.3.2 Labels or instructions