feat: Initialize NxMesh project with Docker, Nginx, PostgreSQL, and Rust backend

- Add Docker Compose configuration for development environment
- Create Nginx configuration files for routing and health checks
- Set up PostgreSQL database with health checks
- Add .dockerignore and .gitignore files to exclude unnecessary files
- Initialize Cargo.toml and Cargo.lock for Rust dependencies
- Include GNU General Public License for project
- Add README.md for project description
- Create Justfile for development workflow commands

.devcontainer/.env.example

@@ -0,0 +1,10 @@
+# Environment Configuration for NxMesh Development
+# Copy this file to .env and customize as needed
+
+# Database
+DATABASE_URL=postgres://postgres:postgres@postgres:5432/nxmesh
+PGHOST=postgres
+PGPORT=5432
+PGUSER=postgres
+PGPASSWORD=postgres
+PGDATABASE=nxmesh