chore: initial project structure and root configuration

Adds root-level config files: solution (.slnx), NuGet, global.json,
Docker Compose files for all services (API, dashboard, website, finder,
admin), environment example, and developer documentation.

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

package-lock.json

@@ -0,0 +1,6 @@
+{
+  "name": "Meezi",
+  "lockfileVersion": 3,
+  "requires": true,
+  "packages": {}
+}