Vendor backend and frontend into the monorepo

The submodule collapse was only half applied: .gitmodules was deleted but
backend/ and frontend/ were still recorded as gitlinks, so none of their
files were tracked. Replace the gitlinks with the real trees.

Also untrack .env (it carried placeholder secrets) in favour of a tracked
.env.example, drop the committed __pycache__, and narrow the blanket *.png
ignore that would have swallowed design assets.

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

frontend/tests/sign-up.spec.ts

@@ -0,0 +1,159 @@
+import { expect, type Page, test } from "@playwright/test"
+
+import { randomEmail, randomPassword } from "./utils/random"
+
+test.use({ storageState: { cookies: [], origins: [] } })
+
+const fillForm = async (
+  page: Page,
+  full_name: string,
+  email: string,
+  password: string,
+  confirm_password: string,
+) => {
+  await page.getByTestId("full-name-input").fill(full_name)
+  await page.getByTestId("email-input").fill(email)
+  await page.getByTestId("password-input").fill(password)
+  await page.getByTestId("confirm-password-input").fill(confirm_password)
+}
+
+const verifyInput = async (page: Page, testId: string) => {
+  const input = page.getByTestId(testId)
+  await expect(input).toBeVisible()
+  await expect(input).toHaveText("")
+  await expect(input).toBeEditable()
+}
+
+test("Inputs are visible, empty and editable", async ({ page }) => {
+  await page.goto("/signup")
+
+  await verifyInput(page, "full-name-input")
+  await verifyInput(page, "email-input")
+  await verifyInput(page, "password-input")
+  await verifyInput(page, "confirm-password-input")
+})
+
+test("Sign Up button is visible", async ({ page }) => {
+  await page.goto("/signup")
+
+  await expect(page.getByRole("button", { name: "Sign Up" })).toBeVisible()
+})
+
+test("Log In link is visible", async ({ page }) => {
+  await page.goto("/signup")
+
+  await expect(page.getByRole("link", { name: "Log In" })).toBeVisible()
+})
+
+test("Sign up with valid name, email, and password", async ({ page }) => {
+  const full_name = "Test User"
+  const email = randomEmail()
+  const password = randomPassword()
+
+  await page.goto("/signup")
+  await fillForm(page, full_name, email, password, password)
+  await page.getByRole("button", { name: "Sign Up" }).click()
+})
+
+test("Sign up with invalid email", async ({ page }) => {
+  await page.goto("/signup")
+
+  await fillForm(
+    page,
+    "Playwright Test",
+    "invalid-email",
+    "changethis",
+    "changethis",
+  )
+  await page.getByRole("button", { name: "Sign Up" }).click()
+
+  await expect(page.getByText("Invalid email address")).toBeVisible()
+})
+
+test("Sign up with existing email", async ({ page }) => {
+  const fullName = "Test User"
+  const email = randomEmail()
+  const password = randomPassword()
+
+  await page.goto("/signup")
+
+  await fillForm(page, fullName, email, password, password)
+  await page.getByRole("button", { name: "Sign Up" }).click()
+
+  await page.goto("/signup")
+
+  await fillForm(page, fullName, email, password, password)
+  await page.getByRole("button", { name: "Sign Up" }).click()
+
+  await page
+    .getByText("The user with this email already exists in the system")
+    .click()
+})
+
+test("Sign up with weak password", async ({ page }) => {
+  const fullName = "Test User"
+  const email = randomEmail()
+  const password = "weak"
+
+  await page.goto("/signup")
+
+  await fillForm(page, fullName, email, password, password)
+  await page.getByRole("button", { name: "Sign Up" }).click()
+
+  await expect(
+    page.getByText("Password must be at least 8 characters"),
+  ).toBeVisible()
+})
+
+test("Sign up with mismatched passwords", async ({ page }) => {
+  const fullName = "Test User"
+  const email = randomEmail()
+  const password = randomPassword()
+  const password2 = randomPassword()
+
+  await page.goto("/signup")
+
+  await fillForm(page, fullName, email, password, password2)
+  await page.getByRole("button", { name: "Sign Up" }).click()
+
+  await expect(page.getByText("The passwords don't match")).toBeVisible()
+})
+
+test("Sign up with missing full name", async ({ page }) => {
+  const fullName = ""
+  const email = randomEmail()
+  const password = randomPassword()
+
+  await page.goto("/signup")
+
+  await fillForm(page, fullName, email, password, password)
+  await page.getByRole("button", { name: "Sign Up" }).click()
+
+  await expect(page.getByText("Full Name is required")).toBeVisible()
+})
+
+test("Sign up with missing email", async ({ page }) => {
+  const fullName = "Test User"
+  const email = ""
+  const password = randomPassword()
+
+  await page.goto("/signup")
+
+  await fillForm(page, fullName, email, password, password)
+  await page.getByRole("button", { name: "Sign Up" }).click()
+
+  await expect(page.getByText("Invalid email address")).toBeVisible()
+})
+
+test("Sign up with missing password", async ({ page }) => {
+  const fullName = ""
+  const email = randomEmail()
+  const password = ""
+
+  await page.goto("/signup")
+
+  await fillForm(page, fullName, email, password, password)
+  await page.getByRole("button", { name: "Sign Up" }).click()
+
+  await expect(page.getByText("Password is required")).toBeVisible()
+})