feat: initial FitCoach Pro lead management app

Next.js 16 app with full CRUD lead management:
- REST API (/api/leads) with GET (pagination), POST, PUT, DELETE (soft delete)
- Zod validation (server + client), Supabase (PostgreSQL)
- Responsive UI: leads table (desktop) + cards (mobile), modal form, toast notifications
- 43 tests (Vitest + React Testing Library): validation, components, pagination
- Docker setup (multi-stage build, health check)
- Supabase migration + 15 seed leads
- Documentation (CLAUDE.md, README, API docs)

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

eslint.config.mjs

@@ -0,0 +1,18 @@
+import { defineConfig, globalIgnores } from "eslint/config";
+import nextVitals from "eslint-config-next/core-web-vitals";
+import nextTs from "eslint-config-next/typescript";
+
+const eslintConfig = defineConfig([
+  ...nextVitals,
+  ...nextTs,
+  // Override default ignores of eslint-config-next.
+  globalIgnores([
+    // Default ignores of eslint-config-next:
+    ".next/**",
+    "out/**",
+    "build/**",
+    "next-env.d.ts",
+  ]),
+]);
+
+export default eslintConfig;