feat: add Astro source code

- Proper Astro project structure
- Nav, hero, GPG badge, status indicator
- Inter + JetBrains Mono fonts

tsconfig.json

@@ -0,0 +1,5 @@
+{
+  "extends": "astro/tsconfigs/strict",
+  "include": [".astro/types.d.ts", "**/*"],
+  "exclude": ["dist"]
+}