Switch to Playwrite US Modern + Imprima fonts

- Headings: Playwrite US Modern (extralight/200 weight)
- Body: Imprima (400 weight)
- Keep Geist Mono for code blocks

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

package-lock.json

@@ -14,6 +14,8 @@
         "@astrojs/sitemap": "^3.6.0",
         "@fontsource/geist-mono": "^5.2.7",
         "@fontsource/geist-sans": "^5.2.5",
+        "@fontsource/imprima": "^5.2.8",
+        "@fontsource/playwrite-us-modern": "^5.2.7",
         "@tailwindcss/vite": "^4.1.13",
         "astro": "^5.13.9",
         "astro-pagefind": "^1.8.5",
@@ -757,6 +759,24 @@
         "url": "https://github.com/sponsors/ayuhito"
       }
     },
+    "node_modules/@fontsource/imprima": {
+      "version": "5.2.8",
+      "resolved": "https://registry.npmjs.org/@fontsource/imprima/-/imprima-5.2.8.tgz",
+      "integrity": "sha512-BdZ+OBW9Wc/P1qYLIbCKNxNgjKE1rn8d4pc0LdGs6uhph7z9nDAp9jtizhuhJgRGDBfxfC7w2jOsiEJ+xP77Xg==",
+      "license": "OFL-1.1",
+      "funding": {
+        "url": "https://github.com/sponsors/ayuhito"
+      }
+    },
+    "node_modules/@fontsource/playwrite-us-modern": {
+      "version": "5.2.7",
+      "resolved": "https://registry.npmjs.org/@fontsource/playwrite-us-modern/-/playwrite-us-modern-5.2.7.tgz",
+      "integrity": "sha512-D1HNZKi3Vm4guvDe9eeXadjWJKREHk6mdGKmMABD1/Q8olcaeG034EZlTlhODNv/eoMFkzOzRAEr8bhaJC+UgQ==",
+      "license": "OFL-1.1",
+      "funding": {
+        "url": "https://github.com/sponsors/ayuhito"
+      }
+    },
     "node_modules/@img/colour": {
       "version": "1.0.0",
       "resolved": "https://registry.npmjs.org/@img/colour/-/colour-1.0.0.tgz",