Phase 1: project foundation for Alpenwerk HR

Scaffolds the Next.js 16 / TypeScript strict / Tailwind v3 app per
NEXTJS_REBUILD_SUPERPROMPT.md, and implements the Foundation slice from
the Phase 1 plan:

- Corrected Supabase schema (supabase/schema.sql): org units, employees,
  history, positions, hire drafts, saved reports, audit log, reorg
  scenarios, role-based profiles, salary-masking view, RLS policies,
  auto-derivation triggers, position-number generator.
- Seed script (supabase/seed.ts): ~800 realistic Austrian employees across
  9 divisions / 16 departments / 35 teams, history, 8 open positions, and
  hr_admin/manager test accounts.
- Supabase clients (lib/supabase/*), design tokens (tailwind.config.ts),
  format/color helpers (lib/format.ts, lib/colors.ts).
- Shared UI kit (components/ui): Avatar, StatusChip, Toast, Modal,
  SlideOver, SegmentedControl, Lookup.
- Auth (login page, Server Actions) and proxy.ts (Next 16's replacement
  for middleware) guarding the authenticated route group.
- Shell (Sidebar, Topbar, NewHireButton stub) and the Dashboard page,
  reading live data via employees_directory.

Employees list/detail, hire wizard, action panels, org chart, positions,
reports, and audit log are deferred to later phases per the plan.

tailwind.config.ts

@@ -0,0 +1,44 @@
+import type { Config } from "tailwindcss";
+
+// Design tokens from spec §7
+const config: Config = {
+  content: ["./app/**/*.{ts,tsx}", "./components/**/*.{ts,tsx}"],
+  theme: {
+    extend: {
+      colors: {
+        brand: {
+          50: "#fdf3f8",
+          100: "#fdeaf3",
+          200: "#f6cfe2",
+          500: "#d6046e",
+          600: "#b0035a",
+          700: "#a30354",
+        },
+        surface: "#f9f1f5",
+        border: {
+          DEFAULT: "#eedde6",
+          subtle: "#f7e8ef",
+        },
+        ink: {
+          DEFAULT: "#2d1c26",
+          body: "#503b47",
+          muted: "#7a636f",
+        },
+        success: { bg: "#dff6dd", text: "#0e700e" },
+        danger: { bg: "#fde7e9", text: "#b10e1c", solid: "#c50f1f" },
+        warning: { bg: "#fff4ce", text: "#835b00" },
+        info: { bg: "#d7f0f0", text: "#00666d" },
+        purple: { bg: "#f0ecf7", text: "#5c2e91" },
+      },
+      borderRadius: {
+        DEFAULT: "8px",
+      },
+      fontFamily: {
+        sans: ["var(--font-nunito)", "system-ui", "sans-serif"],
+      },
+    },
+  },
+  plugins: [],
+};
+
+export default config;