feat: self-serve signup Phase 2 (frontend cutover) (#162)

Co-authored-by: Michael Chihlas <michael@resolutionflow.com>
Co-committed-by: Michael Chihlas <michael@resolutionflow.com>

frontend/src/components/common/__tests__/UpgradePrompt.test.tsx

@@ -0,0 +1,30 @@
+import { describe, it, expect } from 'vitest'
+import { render, screen } from '@testing-library/react'
+import { BrowserRouter } from 'react-router-dom'
+import { UpgradePrompt } from '../UpgradePrompt'
+
+function renderWithRouter(ui: React.ReactElement) {
+  return render(<BrowserRouter>{ui}</BrowserRouter>)
+}
+
+describe('UpgradePrompt', () => {
+  it('renders display name and required plan from catalog', () => {
+    renderWithRouter(<UpgradePrompt feature="psa_integration" />)
+    expect(
+      screen.getByText(/PSA Integration is available on Pro/i),
+    ).toBeInTheDocument()
+  })
+
+  it('CTA navigates to /account/billing/select-plan', () => {
+    renderWithRouter(<UpgradePrompt feature="psa_integration" />)
+    const cta = screen.getByRole('link', { name: /Upgrade to Pro/i })
+    expect(cta).toHaveAttribute('href', '/account/billing/select-plan')
+  })
+
+  it('humanizes unknown feature keys and falls back to Pro', () => {
+    renderWithRouter(<UpgradePrompt feature="some_new_feature" />)
+    expect(
+      screen.getByText(/Some New Feature is available on Pro/i),
+    ).toBeInTheDocument()
+  })
+})