feat: add architecture diagrams page with archify visualizations

- Create /diagrams page with interactive homelab architecture visualizations
- Add deepDive link to homelab project pointing to diagrams
- Include 4 archify diagrams:
  * Talos cluster topology (control planes, GPU worker, storage)
  * GitOps workflow (ArgoCD + Terraform)
  * LLM inference stack (vLLM, Ollama, TEI routing)
  * API request flow sequence diagram
- Support full-screen viewer and embedded grid layout
- Dark/light theme support with responsive design

playwright.config.ts

@@ -0,0 +1,59 @@
+import { defineConfig, devices } from '@playwright/test'
+
+export default defineConfig({
+  testDir: './tests/e2e',
+  fullyParallel: true,
+  forbidOnly: !!process.env.CI,
+  retries: process.env.CI ? 2 : 0,
+  workers: process.env.CI ? 1 : undefined,
+  reporter: [
+    ['html'],
+    ['json', { outputFile: 'test-results/results.json' }],
+    ['junit', { outputFile: 'test-results/results.xml' }],
+    ['list'],
+  ],
+  use: {
+    baseURL: process.env.BASE_URL || 'http://localhost:3000',
+    trace: 'on-first-retry',
+    screenshot: 'only-on-failure',
+    video: 'retain-on-failure',
+  },
+
+  projects: [
+    {
+      name: 'chromium',
+      use: { ...devices['Desktop Chrome'] },
+    },
+    {
+      name: 'firefox',
+      use: { ...devices['Desktop Firefox'] },
+    },
+    {
+      name: 'webkit',
+      use: { ...devices['Desktop Safari'] },
+    },
+
+    // Mobile testing
+    {
+      name: 'Mobile Chrome',
+      use: { ...devices['Pixel 5'] },
+    },
+    {
+      name: 'Mobile Safari',
+      use: { ...devices['iPhone 12'] },
+    },
+
+    // Tablet
+    {
+      name: 'iPad',
+      use: { ...devices['iPad Pro'] },
+    },
+  ],
+
+  webServer: {
+    command: 'pnpm run dev',
+    url: 'http://localhost:3000',
+    reuseExistingServer: !process.env.CI,
+    timeout: 120000,
+  },
+})