Add CONTRIBUTING.md with blog post creation instructions

CONTRIBUTING.md

@@ -0,0 +1,55 @@
+# Contributing to the Spyder Website
+
+1. Create a fork of the repository
+2. Clone it and create a new branch for your changes
+3. Install dependencies with `npm install`
+
+## Creating a Blog Post
+
+1. If the blog post author(s) haven't been added yet:
+    1. Create a new folder in `static/assets/authors` using a simple identifier (no spaces/special characters)
+    2. Inside this folder:
+        - Add a square avatar image (recommended: 512×512px WEBP)
+        - Create `metadata.json` with:
+        ```json
+        {
+            "name": "Author's Display Name",
+            "image": "filename.webp"
+        }
+        ```
+
+2. Create a blog post folder in `src/routes/blog` (name becomes URL slug - lowercase, no spaces)
+
+3. Add a `+page.md` file with this frontmatter:
+```yaml
+---
+title: Blog Post Title # Required
+author: author-id  # Required. For multiple authors, use an array of identifiers
+pub_date: YYYY-MM-DD # Required
+category: Category Name  # Optional
+tags: Tag1, Tag2  # Optional
+summary: Concise overview of content # Required
+---
+```
+
+5. Write content using mdsvex Markdown:
+    - [Never indent code blocks](https://mdsvex.pngwn.io/docs#limitations)
+    - Use standard Markdown syntax for formatting
+
+6. For images:
+    ```markdown
+    ![Meaningful description](image.webp "Optional caption")
+    ```
+    - Store images in the post's folder
+    - All images require *descriptive* alt text (avoid "image of...", "picture of...", "photo of...", etc.)
+
+7. Preview locally with:
+```bash
+npm run dev
+```
+    - Verify post appears at `/blog/`
+    - Check author metadata and image display
+
+8. There is no need to build for production, the workflow will run the build on GitHub Actions.
+
+9. Create PR against upstream `main` branch.

README.md

@@ -2,6 +2,7 @@
 
 Minimal static [SvelteKit](https://kit.svelte.dev/) set-up made deployable to [GitHub Pages](https://metonym.github.io/sveltekit-gh-pages/). Based on [sveltekit-gh-pages](https://metonym.github.io/sveltekit-gh-pages/)
 
+- Made with Svelte 4
 - PostCSS framework provided by [TailwindCSS](https://tailwindcss.com/)
 - Icons from the [Svelte Icons Pack](https://leshak.github.io/svelte-icons-pack/)
 - Markdown files processed with [mdsvex](https://mdsvex.pngwn.io/)
@@ -35,3 +36,7 @@ npm run preview
 ```
 
 And preview your built site at [https://localhost:5174](https://localhost:5174)
+
+## Contributing
+
+See [CONTRIBUTING.md](CONTRIBUTING.md)