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+# UX-audit polish follow-up (dark-mode long-tail + IA + forms)
+
+**Date:** 2026-07-11
+**Status:** Idea — deferred remainder of the 2026-07-11 UX audit, whose high/medium findings shipped across PRs #616–#620
+**Priority:** P2
+**Origin:** UX audit (5-agent sweep, 2026-07-11). The five fix PRs — #616 (wire values), #617 (resilience), #618 (a11y), #619 (IA), #620 (theming/dark mode) — each deferred a low-severity tail, tracked here.
+**Depends on:** None (all build on the merged PRs above)
+
+## Problem
+
+The UX audit's high- and medium-severity findings are fixed and merged. A
+low-severity tail was deliberately deferred to keep each PR reviewable. The
+sharpest item is that **dark mode is now reachable (toggle shipped, primitives
+migrated + Playwright-verified) but not yet swept across the long tail** — some
+ad-hoc hardcoded colors remain light-only, so a human dark-mode QA pass is
+needed before calling dark mode 100% done.
+
+## Proposed capabilities
+
+### Dark-mode completion (from #620)
+
+- Sweep the ~49 `text-blue-600` link occurrences (31 files) to a
+  `text-primary`/`buttonVariants({variant:'link'})` token so links theme in
+  dark mode; sweep any remaining `bg-*-50` callouts to the new `<Alert>`
+  primitive.
+- Migrate the three Recharts charts off hardcoded hex series colors to a
+  theme-aware palette, and add axis labels + units (Y is the objective metric,
+  X is `trial_number` — currently unlabeled).
+- **Human dark-mode QA pass** across every route/surface (the token migration
+  is correct-by-construction, but the long tail needs eyes).
+
+### IA & navigation tail (from #619)
+
+- Empty-state CTA parity: add a `primaryCta` to the studies / query-sets /
+  templates empty states (wire the page's create handler through, mirroring
+  `clusters-table`'s `onRegisterCluster`).
+- Cluster-tree breadcrumb consistency: extract the leaf page's breadcrumb into
+  a shared `<ClusterTreeBreadcrumb>` and render it on the intermediate
+  index-summary + documents-list pages (F5).
+- Reverse "used by" links on template / query-set / judgment-list detail pages
+  (mirror `StudiesByClusterTable`); make template `parent_id` a link (F7).
+- Resolve the query-set→cluster link to the cluster **name** (currently links
+  but shows the raw UUID — needs a `useCluster` call via a sub-component).
+
+### Forms & polish (from #617/#618)
+
+- Comprehensive `aria-invalid`/`aria-describedby` association across the large
+  study-creation wizard's fields (the small dialogs were done in #618; wizard
+  errors are announced via `role="alert"` but not yet field-associated).
+- Centralized `formatDateTime()` (and a companion `formatNumber()`) util to
+  replace the ad-hoc `toLocaleString()` calls for consistent, locale-stable
+  formatting. Note: only the **date-time** `toLocaleString()` calls belong in
+  `formatDateTime()`; some occurrences format **numbers** (e.g.
+  `doc_count.toLocaleString()` in `create-study-modal.tsx`) and belong in
+  `formatNumber()` instead — don't blanket-replace.
+- Per-list `errorMessage`/`onRetry` wiring on the DataTable error state (the
+  optional props landed in #617 with a page-reload fallback; wire real
+  `query.error.message` + `query.refetch` through the consumer tables).
+
+## Scope signals
+
+- **Backend:** none.
+- **Frontend:** `ui/src/components/**` (primitives + charts + tables + wizard),
+  `ui/src/app/**` (breadcrumb pages, empty-state CTAs).
+- **Migration:** none.
+- **Config:** none.
+- **Audit events:** N/A.
+
+## Why deferred
+
+All items are low-severity polish. Each was split out of its parent PR to keep
+that PR focused and reviewable; the dark-mode long-tail sweep in particular
+benefits from a dedicated human visual-QA pass rather than being rushed into
+the theming PR. None blocks the shipped high/medium fixes.
+
+## Relationship to other work
+
+Direct continuation of PRs #616–#620 (all merged, `implemented_features`-bound
+once finalized). No conflicts; purely additive polish.