Move the console onto ReUI PRO

Install ReUI (MCP, skill, @reui registry, Tailwind v4, shadcn base-nova) and move
the shared UI onto it: Button, Tag, Check, Input/Textarea, Segmented, Alert, Panel,
Dialog, Tooltip, Menu and Select (Popover), Toast (sonner), the Table frame
(DataGrid), the Dashboard KPI strip, the shnt Ops palette, Geist and the type scale.

Design only: behaviour, texts and roles are unchanged. Tests that asserted the old
DOM were updated; the tests now format numbers in English wherever they run.
docs/reui-migration-plan.md records the plan and its decisions.

Co-Authored-By: Claude Sonnet 5.5 <noreply@anthropic.com>

dev/css-duplicated.mjs

@@ -0,0 +1,90 @@
+/*
+The same thing, written in two modules.
+
+`css-dead.mjs` answers whether a rule is unused. This one answers something
+different: whether the SAME rule is written more than once. That is the defect
+that produces drift (two copies that start identical and stop being identical),
+and no screen-by-screen review catches it, because on each screen, taken alone,
+everything looks right.
+
+Measured before fixing it, it found 27 groups, and out of those came, among
+others:
+
+  · eleven `<textarea>` elements painting their own box by hand, with radius 6
+    instead of 8 and without the inset shadow every other field carries;
+  · the inline `<code>` in five modules and the intro paragraph in five, one of
+    them at 1.65 line-height against 1.6 in the other four;
+  · the `<details>` chevron hand-encoded as an SVG in a `data:` URI, in two
+    modules, with a different stroke width from every other icon;
+  · the count under a table sitting at four different distances.
+
+    node dev/css-duplicated.mjs
+
+## How to read it
+
+It groups by rule BODY, ignoring `composes`, and only shows bodies that appear in
+more than one module. That leaves out what is already shared (a class that
+composes from another repeats nothing) and leaves in three things that are NOT
+defects, so look before you touch:
+
+  · **Applying the same token.** Two components with `background: var(--acc)`
+    duplicate nothing: the token IS the single source, and `composes` cannot even
+    reach a pseudo-class or an attribute selector, which is where nearly all of
+    these come from. Real example: the highlight on a menu option and the one on
+    a dropdown option.
+  · **Generic layout coincidences.** `display:flex; flex-direction:column;
+    gap:var(--s-9)` shows up in a column on About, another on the Dashboard and
+    the Login form. They are not the same thing; there are just few ways to stack
+    three elements.
+  · **The same responsive collapse.** `grid-template-columns: minmax(0,1fr)`
+    inside a media query means "one column when narrow", and every grid in the
+    console says it.
+
+The minimum body length is there so the output is not drowned in single-property
+rules, which are almost always one of the three cases above.
+*/
+import { readFileSync, readdirSync, statSync } from 'node:fs'
+import { join } from 'node:path'
+
+const ROOT = join(import.meta.dirname, '..', 'src')
+const MINIMUM = Number(process.env.MINIMO ?? 28)
+
+function files(dir, acc = []) {
+  for (const e of readdirSync(dir)) {
+    const p = join(dir, e)
+    if (statSync(p).isDirectory()) files(p, acc)
+    else if (e.endsWith('.module.css')) acc.push(p)
+  }
+  return acc
+}
+
+const groups = new Map()
+
+for (const mod of files(ROOT)) {
+  const css = readFileSync(mod, 'utf8').replaceAll(/\/\*[\s\S]*?\*\//g, '')
+  for (const m of css.matchAll(/([^{}]+)\{([^{}]+)\}/g)) {
+    const selector = m[1].trim().split('\n').at(-1).trim()
+    /* Normalised: no spaces and sorted, so two identical rules written with
+       different formatting, or with the properties in another order, match. */
+    const body = m[2]
+      .split(';')
+      .map((d) => d.trim().replaceAll(' ', ''))
+      .filter((d) => d && !d.startsWith('composes'))
+      .sort()
+      .join(' ')
+    if (body.length < MINIMUM) continue
+    if (!groups.has(body)) groups.set(body, [])
+    groups.get(body).push({ mod: mod.slice(ROOT.length + 1), selector })
+  }
+}
+
+const repeated = [...groups]
+  .filter(([, places]) => new Set(places.map((s) => s.mod)).size > 1)
+  .sort((a, b) => b[1].length - a[1].length)
+
+for (const [body, places] of repeated) {
+  console.log(`\n[${places.length}] ${body}`)
+  for (const s of places) console.log(`     ${s.mod}  ${s.selector}`)
+}
+
+console.log(`\n${repeated.length} rule bodies written in more than one module`)