Add the web app, seed data, and user-selectable theming

apps/web — React, Vite, Tailwind, shadcn-idiom components. Mobile Safari is a
first-class target, not an afterthought:

- Two navigation treatments rather than one compromise. A bottom tab bar on
  phones, because the top of a large phone is out of thumb reach; a persistent
  sidebar from lg upward, so an iPad in portrait gets it too.
- Safe-area insets throughout, so the tab bar clears the home indicator and the
  last row of a list is actually reachable.
- Inputs are pinned to a 16px minimum, which is the correct fix for Safari
  zooming on focus. user-scalable=no is not used: it breaks pinch-zoom for
  everyone and recent iOS ignores it anyway.
- The pipeline board becomes a stage picker on phones. An eight-column board
  scrolling horizontally on a 390px screen is technically responsive and
  practically useless.

Theming: users pick an accent and the whole interface re-tints. Accent values
live once, in @pig/core, and are written onto the root element at runtime —
there is no CSS copy to drift from the TypeScript. Preferences are stored
server-side so they follow a person between laptop and phone, mirrored into
localStorage only so the pre-paint script can avoid a white flash. Status
colours stay fixed regardless of accent: if "at risk" re-tinted to whatever
someone picked, the signal would be gone.

Seed data is public research, every record carrying a confidence grade and a
source URL. No email addresses are seeded or inferred — none are published, and
guessing them from a name and a domain is unreliable and rude. Authorship is
not promoted to employment: contributors, residency participants and alumni are
recorded as what the evidence actually shows, and a name that could not be
sourced at all is listed as unresolved rather than invented.

Three defects found and fixed by actually running it rather than assuming:

1. The seed was not idempotent. onConflictDoNothing() with no target is a no-op
   without a matching unique constraint, so a second run duplicated 27
   contacts. There is deliberately no unique index on (account, name) — two
   people at one company can share a name — so idempotency is enforced in the
   seed instead of by bending the schema.
2. /capacity scrolled sideways on a phone. Grid items default to
   min-width:auto and `truncate` sets nowrap, so a long title became
   unshrinkable content and widened the track. Fixed with min-w-0 on every
   truncating grid child.
3. The idle-capacity alert silently failed to fire at exactly 80% utilisation,
   losing a float comparison against a 0.2 threshold. Moved to 0.15, which is
   also a more sensible line for "worth attention".

The worked example is tuned to teach rather than to flatter: 70% sold at a 53%
markup lands at +6.7% margin with 20% still idle, so both the healthy number
and the alert are visible. Drop the sold share to 55% and the same block goes
underwater — that sensitivity is the argument for the product.

Verified in a real browser at 393px and 1440px, light and dark: zero horizontal
overflow on every route, zero console errors.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>

apps/web/tailwind.config.js

@@ -0,0 +1,33 @@
+/** @type {import('tailwindcss').Config} */
+export default {
+  darkMode: ['class', '[data-theme="dark"]'],
+  content: ['./index.html', './src/**/*.{ts,tsx}'],
+  theme: {
+    extend: {
+      colors: {
+        // Every colour resolves through a CSS variable so the user's chosen
+        // accent re-tints the whole interface without a rebuild.
+        bg: 'hsl(var(--bg))',
+        surface: 'hsl(var(--surface))',
+        'surface-2': 'hsl(var(--surface-2))',
+        border: 'hsl(var(--border))',
+        fg: 'hsl(var(--fg))',
+        muted: 'hsl(var(--muted))',
+        accent: 'hsl(var(--accent))',
+        'accent-fg': 'hsl(var(--accent-fg))',
+        'accent-on': 'hsl(var(--accent-on))',
+        'accent-subtle': 'hsl(var(--accent-subtle))',
+        positive: 'hsl(var(--positive))',
+        warning: 'hsl(var(--warning))',
+        danger: 'hsl(var(--danger))',
+        info: 'hsl(var(--info))',
+      },
+      fontFamily: {
+        sans: ['ui-sans-serif', 'system-ui', '-apple-system', 'Segoe UI', 'Inter', 'sans-serif'],
+        mono: ['ui-monospace', 'SFMono-Regular', 'Menlo', 'monospace'],
+      },
+      borderRadius: { lg: '0.75rem', xl: '1rem' },
+    },
+  },
+  plugins: [],
+};