Add Playwright E2E testing infrastructure

- New apps/e2e workspace with @playwright/test
- playwright.config.ts targeting Docker Compose stack (http://localhost:8080)
- navigation.spec.ts: smoke tests for all pages
- book.spec.ts: full booking wizard happy-path with API mocking
- clients.spec.ts: client list and detail panel tests
- CI job: spins up docker compose, installs Playwright chromium, runs tests
- Playwright report uploaded as artifact on failure
- README docs for running E2E tests locally

Closes #40

Co-Authored-By: Paperclip <noreply@paperclip.ing>

pnpm-lock.yaml

@@ -69,6 +69,12 @@ importers:
         specifier: ^3.0.4
         version: 3.2.4(@types/node@22.19.15)(jsdom@26.1.0)(terser@5.46.1)(tsx@4.21.0)
 
+  apps/e2e:
+    devDependencies:
+      '@playwright/test':
+        specifier: ^1.50.1
+        version: 1.58.2
+
   apps/web:
     dependencies:
       '@groombook/types':
@@ -1409,6 +1415,11 @@ packages:
     resolution: {integrity: sha512-+1VkjdD0QBLPodGrJUeqarH8VAIvQODIbwh9XpP5Syisf7YoQgsJKPNFoqqLQlu+VQ/tVSshMR6loPMn8U+dPg==}
     engines: {node: '>=14'}
 
+  '@playwright/test@1.58.2':
+    resolution: {integrity: sha512-akea+6bHYBBfA9uQqSYmlJXn61cTa+jbO87xVLCWbTqbWadRVmhxlXATaOjOgcBaWU4ePo0wB41KMFv3o35IXA==}
+    engines: {node: '>=18'}
+    hasBin: true
+
   '@rolldown/pluginutils@1.0.0-beta.27':
     resolution: {integrity: sha512-+d0F4MKMCbeVUJwG96uQ4SgAznZNSq93I3V+9NHA4OpvqG8mRCpGdKmK8l/dl02h2CCDHwW2FqilnTyDcAnqjA==}
 
@@ -2331,6 +2342,11 @@ packages:
     resolution: {integrity: sha512-hcg3ZmepS30/7BSFqRvoo3DOMQu7IjqxO5nCDt+zM9XWjb33Wg7ziNT+Qvqbuc3+gWpzO02JubVyk2G4Zvo1OQ==}
     engines: {node: '>=10'}
 
+  fsevents@2.3.2:
+    resolution: {integrity: sha512-xiqMQR4xAeHTuB9uWm+fFRcIOgKBMiOBP+eXiyT7jsgVCq1bkVygt00oASowB7EdtpOHaaPgKt812P9ab+DDKA==}
+    engines: {node: ^8.16.0 || ^10.6.0 || >=11.0.0}
+    os: [darwin]
+
   fsevents@2.3.3:
     resolution: {integrity: sha512-5xoDfX+fL7faATnagmWPpbFtwh/R77WmMMqqHGS65C3vvB0YHrgF+B1YmZ3441tMj5n63k0212XNoJwzlhffQw==}
     engines: {node: ^8.16.0 || ^10.6.0 || >=11.0.0}
@@ -2890,6 +2906,16 @@ packages:
     resolution: {integrity: sha512-5gTmgEY/sqK6gFXLIsQNH19lWb4ebPDLA4SdLP7dsWkIXHWlG66oPuVvXSGFPppYZz8ZDZq0dYYrbHfBCVUb1Q==}
     engines: {node: '>=12'}
 
+  playwright-core@1.58.2:
+    resolution: {integrity: sha512-yZkEtftgwS8CsfYo7nm0KE8jsvm6i/PTgVtB8DL726wNf6H2IMsDuxCpJj59KDaxCtSnrWan2AeDqM7JBaultg==}
+    engines: {node: '>=18'}
+    hasBin: true
+
+  playwright@1.58.2:
+    resolution: {integrity: sha512-vA30H8Nvkq/cPBnNw4Q8TWz1EJyqgpuinBcHET0YVJVFldr8JDNiU9LaWAE1KqSkRYazuaBhTpB5ZzShOezQ6A==}
+    engines: {node: '>=18'}
+    hasBin: true
+
   possible-typed-array-names@1.1.0:
     resolution: {integrity: sha512-/+5VFTchJDoVj3bhoqi6UeymcD00DAwb1nJwamzPvHEszJ4FpF6SNNbUbOS8yI56qHzdV8eK0qEfOSiodkTdxg==}
     engines: {node: '>= 0.4'}
@@ -4706,6 +4732,10 @@ snapshots:
   '@pkgjs/parseargs@0.11.0':
     optional: true
 
+  '@playwright/test@1.58.2':
+    dependencies:
+      playwright: 1.58.2
+
   '@rolldown/pluginutils@1.0.0-beta.27': {}
 
   '@rollup/plugin-babel@5.3.1(@babel/core@7.29.0)(@types/babel__core@7.20.5)(rollup@2.80.0)':
@@ -5716,6 +5746,9 @@ snapshots:
       jsonfile: 6.2.0
       universalify: 2.0.1
 
+  fsevents@2.3.2:
+    optional: true
+
   fsevents@2.3.3:
     optional: true
 
@@ -6273,6 +6306,14 @@ snapshots:
 
   picomatch@4.0.3: {}
 
+  playwright-core@1.58.2: {}
+
+  playwright@1.58.2:
+    dependencies:
+      playwright-core: 1.58.2
+    optionalDependencies:
+      fsevents: 2.3.2
+
   possible-typed-array-names@1.1.0: {}
 
   postcss@8.5.8: