docs: Add Podman development recommendations to Copilot instructions

- Add 'Recommended Development Setup' section highlighting Podman as the recommended development approach
- Organize Commands section into two subsections: 'Local Development (with Podman)' and 'Direct Commands (without Podman)'
- Include examples for podman compose commands (up --build, up -d, exec)
- Reference README.md for detailed container setup instructions

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

.github/copilot-instructions.md

@@ -28,7 +28,23 @@ This is a personal blog named "Naputo" built with Astro and Preact. The blog is
 
 ## Development Guidelines
 
+### Recommended Development Setup
+
+**Development via Podman (Recommended)**: This repository is designed to be developed inside a Podman container for consistency and reproducibility. See README.md for complete container setup instructions.
+
+- Run `podman compose up --build` to start development
+- Run commands in the container with `podman compose exec app <command>`
+- This keeps your host environment clean and ensures reproducible builds
+
 ### Commands
+
+#### Local Development (with Podman - Recommended)
+- `podman compose up --build`: Start development container with auto-rebuild
+- `podman compose up -d`: Start development container in background
+- `podman compose exec app npm run dev`: Start dev server inside container
+- `podman compose exec app npm run build`: Build inside container
+
+#### Direct Commands (without Podman)
 - `npm install`: Install dependencies
 - `npm run dev`: Start local development server at `localhost:4321`
 - `npm run build`: Build production site to `./dist/`