feat(auth): add configurable email verification enforcement

Auth:RequireEmailVerification (default off) gates whether local
register requires confirming email before login. OAuth new-user paths
are untouched -- Google/Microsoft already assert a verified email.
Adds verify-email and resend-verification-email endpoints, mirroring
the existing reset-password enumeration-avoidance and rate-limiting
patterns, plus a login-embedded resend affordance and a verify-email
landing page on the frontend.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

job-tracker-ui/src/App.tsx

@@ -31,6 +31,7 @@ import LoginPage from "./views/LoginPage";
 import LandingPage from "./views/LandingPage";
 import ForgotPasswordPage from "./views/ForgotPasswordPage";
 import ResetPasswordPage from "./views/ResetPasswordPage";
+import VerifyEmailPage from "./views/VerifyEmailPage";
 import RouteErrorPage from "./views/RouteErrorPage";
 import { api } from "./api";
 import { resolveCaptureUrl } from "./captureUrl";
@@ -366,6 +367,7 @@ export default function App() {
     { path: "/login", element: <LoginPage />, errorElement: <RouteErrorPage /> },
     { path: "/forgot-password", element: <ForgotPasswordPage />, errorElement: <RouteErrorPage /> },
     { path: "/reset-password", element: <ResetPasswordPage />, errorElement: <RouteErrorPage /> },
+    { path: "/verify-email", element: <VerifyEmailPage />, errorElement: <RouteErrorPage /> },
     { path: "/*", element: <Shell jobPageSize={jobPageSize} setJobPageSize={setJobPageSize} jobColumns={jobColumns} setJobColumns={setJobColumns} themeMode={themeMode} onThemeModeChange={onThemeModeChange} />, errorElement: <RouteErrorPage /> },
   ], { future: { v7_relativeSplatPath: true } }), [jobColumns, jobPageSize, themeMode]);