fix(web): settings page layout pass (FE-7)

- Section header (h2 + description) and section blocks as h3; unified
  block padding and title size
- Global settings forms use label-left / control-right rows, stacked
  below md; control width fixed by type (number short, text/select
  medium, wide/textarea full)
- Per-block SaveBar pinned at the block end with dirty hint; naming
  template saves moved from the header to the bar
- Console shell uses overflow-x-clip so the sticky header and sticky
  section nav actually stick; anchor jumps re-align while async content
  loads and land below the header
- Section content uses a single minmax(0,1fr) column so wide tables
  scroll inside their card instead of widening the page
- useSettings fills missing keys from DEFAULT_SETTINGS so an older
  backend no longer crashes the metadata section

Co-Authored-By: Claude Opus 5.5 <[email protected]>

apps/web/app/components/settings/account.tsx

@@ -189,7 +189,7 @@ export function AccountSection() {
   const session = useSession();
   const cookie = !!session.data?.expiresAt;
   return (
-    <div className="grid gap-8">
+    <div className="grid grid-cols-1 gap-8">
       <PasswordBlock disabled={!cookie} />
       <TotpBlock disabled={!cookie} />
       <PasskeyBlock disabled={!cookie} />