Add spellchecking to pre-commit hooks and linting workflow

.github/workflows/lint.yml

@@ -27,7 +27,8 @@ jobs:
           cache-dependency-path: "**/package-lock.json"
           node-version: "18"
 
-      - name: Run linter
+      - name: Run linter and spellcheck
         run: |
           npm ci
           npm run lint
+          npm run spellcheck

README.md

@@ -47,6 +47,12 @@ Please follow the following (very brief) style guide:
 - Use code blocks for all commands. Don't write them in-line.
 - Avoid long paragraphs - this documentation should be to-the-point and instructional.
 
+### Spellchecker
+
+We use `cspell` for spellchecking. It will run as a pre-commit hook and in the CI pipeline.
+Spellchecking ignores single and multi-line code snippets. If required, you can add custom words
+(e.g. proper nouns and technical terms) to `custom-words.txt`.
+
 ### Conditional Content
 
 The Contributing Docs site is used both for internal and external contributors. To this end we've

cspell.yaml

@@ -0,0 +1,36 @@
+---
+dictionaries:
+  - custom-words
+dictionaryDefinitions:
+  - name: custom-words
+    path: ./custom-words.txt
+    addWords: true
+patterns:
+  # Ignore multi-line code blocks
+  # Ref: https://cspell.org/configuration/patterns/
+  # Modified to avoid matching line breaks before/after which had unexpected results
+  - name: markdown_code_block
+    pattern: |
+      /
+          ^[ \t]*     # match optional whitespace before the ```
+          (`{3}).*    # match the ``` and any optional language specification afterwards
+          [\s\S]*?    # the block of code
+          ^[ \t]*     # match optional whitespace before the ```
+          \1          # end of the block
+      /gmx
+
+  # Ignore inline code blocks
+  - name: markdown_code_inline
+    pattern: |
+      /
+          `           # match the opening `
+          .*?         # match any characters, lazily (so that we stop at the next tilde)
+          `           # match the closing `
+      /gx
+languageSettings:
+  - languageId:
+      - markdown
+      - mdx
+    ignoreRegExpList:
+      - markdown_code_block
+      - markdown_code_inline

custom-words.txt

@@ -0,0 +1,54 @@
+# Custom dictionary for spellchecking
+# Before adding a word here, consider whether you can put it in a single (`) or multiline (```) code snippet instead,
+# as they are automatically ignored by the spellchecker
+
+Bitwarden
+bytemark
+CQRS
+dockerized
+hotfix
+hotfixes
+hotfixed
+inet
+Iterm
+jslib
+jumpcloud
+keychain
+keyserver
+LDIF
+LLDB
+Mailcatcher
+minio
+MVVM
+NGRX
+Omnisharp
+opid
+passcode
+passwordless
+PNSs
+proxied
+roadmap
+roadmaps
+SCIM
+SDET
+signtool
+signup
+sqlcmd
+TOTP
+Yellowpages
+CODEOWNERS
+SDLC
+subprocessor
+Gitter
+IntelliJ
+WCAG
+pinentry
+refactorings
+toolset
+keypair
+onboarded
+OIDCS
+oktapreview
+Xcodes.app
+YubiKey
+Yubico