feat(e2e): ajouter tests Playwright flux utilisateur core (login, workspace, palette, dashboard)

- e2e/flowdeck_e2e_final.spec.js: 4 tests E2E validés
  1. Login UI local (#email, #password, .btn-primary)
  2. Créer workspace local + entrer (modal .dialog-input)
  3. Ouvrir palette Ctrl+K et valider 'Créer une collection'
  4. Dashboard accessible
- e2e/ : package.json, playwright.config.js, install chromium

e2e/explore.spec.js

@@ -0,0 +1,34 @@
+const { test } = require('@playwright/test');
+
+const BASE = process.env.FD_BASE_URL || 'http://localhost:8080';
+const USER = process.env.FD_USER || '[email protected]';
+const PASS = process.env.FD_PASS || 'e2e-secret-123';
+
+test('explore: login UI + home', async ({ page }) => {
+  await page.goto(`${BASE}/auth/login?provider=local`);
+  await page.waitForTimeout(800);
+  console.log('LOGIN PAGE title:', await page.title());
+  // List inputs / buttons on login page
+  const inputs = await page.evaluate(() =>
+    [...document.querySelectorAll('input')].map(i => ({
+      id: i.id, name: i.name, type: i.type, placeholder: i.placeholder,
+    }))
+  );
+  console.log('LOGIN INPUTS:', JSON.stringify(inputs));
+  const btns = await page.evaluate(() =>
+    [...document.querySelectorAll('button,[type=submit]')].map(b => ({
+      text: (b.innerText||'').trim().slice(0,30), cls: b.className.slice(0,30),
+    }))
+  );
+  console.log('LOGIN BUTTONS:', JSON.stringify(btns));
+  await page.screenshot({ path: 'shots/login.png' });
+
+  // Try login with UI
+  await page.fill('input[type=email], input[name=email], #email', USER).catch(()=>{});
+  // fallback: fill first text input
+  await page.fill('input[type=password], input[name=password], #password', PASS).catch(()=>{});
+  await page.screenshot({ path: 'shots/login_filled.png' });
+  await page.waitForTimeout(300);
+  console.log('AFTER FILL inputs value check:');
+  console.log(await page.evaluate(() => [...document.querySelectorAll('input')].map(i=>[i.type, i.value])));
+});