chore: Add GitHub Action for spell checking with cspell

.github/workflows/spellcheck.yml

@@ -0,0 +1,20 @@
+name: Spell Check
+
+on:
+  push:
+    branches:
+      - main
+  pull_request: {}
+
+permissions:
+  contents: read
+
+jobs:
+  spellcheck:
+    name: Check Spelling
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+      - uses: streetsidesoftware/cspell-action@v6
+        with:
+          files: "**/*.{html,md}"

CONTRIBUTING.md

@@ -1,7 +1,7 @@
 # Digital Credentials: Federated Identity on the Web Working Group
 
 This repository is being used for work in the W3C Federated Identity on the Web Working Group, governed by the [W3C Patent Policy](http://www.w3.org/Consortium/Patent-Policy-20040205/) and
-[Spftware and Document License](https://www.w3.org/copyright/software-license-2023/). To contribute, you must 
+[Software and Document License](https://www.w3.org/copyright/software-license-2023/). To contribute, you must 
 either participate in the relevant W3C Working Group or make a [non-member patent licensing
  commitment](https://www.w3.org/policies/process/#contributor-license).
 
@@ -23,3 +23,18 @@ If you added a contributor by mistake, you can remove them in a comment with:
 
 If you are making a pull request on behalf of someone else but you had no part in designing the
 feature, you can remove yourself with the above syntax.
+
+## Spell Checking
+
+This repository uses [cspell](https://cspell.org/) for spell checking. Spelling is automatically checked on pull requests via GitHub Actions.
+
+### Using cspell with Visual Studio Code
+
+To enable spell checking in VS Code:
+
+1. Install the [Code Spell Checker](https://marketplace.visualstudio.com/items?itemName=streetsidesoftware.code-spell-checker) extension by streetsidesoftware.
+2. The extension will automatically use the `cspell.json` configuration file in this repository.
+3. Spelling errors will be highlighted with a blue squiggly underline.
+4. To add a word to the project dictionary, use the Quick Fix menu (Ctrl+. or Cmd+.) and select "Add word to cspell.json".
+
+Custom dictionaries for this project are located in the `.cspell/` directory.