Contribution guidelines; moved .vscode/settings.json to settings.json.example; added extensions.json

.gitignore

@@ -20,3 +20,7 @@ pnpm-debug.log*
 
 # macOS-specific files
 .DS_Store
+
+# Do allow versioning of .vscode/ directory itself, if we want to version some example files or
+# extensions.json.
+.vscode/settings.json

.vscode/extensions.json

@@ -1,4 +1,11 @@
 {
-  "recommendations": ["astro-build.astro-vscode"],
+  "recommendations": [
+    "astro-build.astro-vscode",
+    "stkb.rewrap",
+    "bierner.markdown-preview-github-styles",
+    "davidanson.vscode-markdownlint",
+    "drmerfy.overtype",
+    "streetsidesoftware.code-spell-checker"
+  ],
   "unwantedRecommendations": []
 }

.vscode/settings.json.example

@@ -0,0 +1,10 @@
+{
+    "editor.formatOnSave": false,
+    "editor.rulers": [
+        100
+    ],
+    "markdownlint.config": {
+        "MD013": false,
+        "MD025": false
+    }
+}

CONTRIBUTING.md

@@ -0,0 +1,88 @@
+# Rules of thumb
+
+- Leave the last line empty. It makes `git diff` (and any `diff`) easier to review when the last
+  line is modified/appended.
+- Wrap lines. Suggest wrapping to 100 characters, which is the [Rust fmt
+  standard](https://rust-lang.github.io/rustfmt/?version=master&search=#max_width).
+
+# VS Code
+
+If you use VS Code, suggest
+
+- Do NOT add/commit your `.vscode/settings.json`. Instead,
+  - add `.vscode/settings.json` (but NOT the whole `.vscde` directory) to `.gitignore`, and
+  - share any suggested settings in `.vscode/settings.json.example` and add that to git.
+
+- [Rewrap](https://marketplace.visualstudio.com/items?itemName=stkb.rewrap) for rewrapping comments
+  and documentation.
+
+  Rewrap doesn't touch the source code itself, only comments (and `.md` files). It preserves
+  Markdown formatting in comments (even though it understands only one of Markdown
+  formatting/indentation way of nested lists, see source code of this file below). You can apply
+  Rewrap to Markdown (`.md`) files, too.
+
+  If you edit existing content a lot, do NOT have Rewrap set to automatic, but use Alt+Q to rewrap
+  the current comment section (consecutive lines of comments that include the current line). Ctrl+A
+  Alt+Q rewraps all comments (in the current file).
+
+- [Markdownlint](https://marketplace.visualstudio.com/items?itemName=DavidAnson.vscode-markdownlint)
+  for Markdown checks. But, suggest turning off
+
+  - [MD013 to allow long lines, for example: Markdown
+tables](https://github.com/DavidAnson/markdownlint/blob/main/doc/md013.md)
+  - [MD025 to allow multiple H1
+headings](https://github.com/DavidAnson/markdownlint/blob/main/doc/md025.md)
+
+  How? Either by having the following at the top of the `.md` files:
+
+  ```html
+  <!-- markdownlint-disable MD013 -->
+  <!-- markdownlint-disable MD025 -->
+  ```
+
+  Or configure in Ctrl+Shift+P > Preferences: Open User Settings (JSON):
+
+  ```json
+    "editor.rulers": [
+        100
+    ],
+    "markdownlint.config": {
+        "MD013": false,
+        "MD025": false
+    }
+  ```
+
+- [Code Spell
+  Checker](https://marketplace.visualstudio.com/items?itemName=streetsidesoftware.code-spell-checker)
+
+- [Overtype](https://marketplace.visualstudio.com/items?itemName=drmerfy.overtype) is excellent when
+  editing tables, or any preformatted text.
+
+- [Markdown Preview Github
+  Styling](https://marketplace.visualstudio.com/items?itemName=bierner.markdown-preview-github-styles)
+
+- Preview Markdown in a separate tab with `Ctrl + Shift + P` > Markdown: Open Preview.
+- Unless you're editing a small file, suggest to __disable__ both:
+  - Settings > Markdown > Preview > Scroll Editor With Preview, and 
+  - Settings > Markdown > Preview > Scroll Preview With Editor.
+
+  Or configure in Ctrl+Shift+P > Preferences: Open User Settings (JSON):
+
+  ```json
+    "markdown.preview.scrollPreviewWithEditor": false,
+    "markdown.preview.scrollEditorWithPreview": false
+  ```
+
+  And/or preview Markdown in Firefox (see below).
+
+- Please, share other VS Code extensions by adding them to `.vscode/extensions.json`.
+
+# Firefox
+
+Markdown Preview in VS Code sometimes scrolls the (Markdown) source code up or down.
+
+For smooth preview, install [Markdown Viewer
+Webext](https://addons.mozilla.org/en-US/firefox/addon/markdown-viewer-webext/) in Firefox. Also
+configure Firefox [on Linux/Mac
+OS](https://github.com/Cimbali/markdown-viewer#support-for-local-files-on-linux-and-macos) so it
+applies this extension to local Markdown files.