add spellchecker, some doc clean up (#22)

we will not block merges based on spelling yet, as there are many

spell checking should work in the devcontainer as it does in CI, except in CI we're only checking the docs folder

.devcontainer/devcontainer.json

@@ -8,7 +8,9 @@
                 "Redocly.openapi-vs-code",
                 "emeraldwalk.RunOnSave",
                 "42Crunch.vscode-openapi",
-                "stoplight.spectral"
+                "stoplight.spectral",
+                "pomdtr.excalidraw-editor",
+                "streetsidesoftware.code-spell-checker"
             ]
         }
     },

.github/workflows/spellcheck.yaml

@@ -0,0 +1,24 @@
+name: 'Check spelling'
+on: # rebuild any PRs and main branch changes
+  push:
+    branches:
+      - 1.0.0*
+  pull_request:
+    branches:
+      - 1.0.0*
+
+jobs:
+  spellcheck: # run the action
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+      - uses: streetsidesoftware/cspell-action@v5
+        with:
+          incremental_files_only: false
+          config: 'cspell.json'
+          # eventually we intend to fail the build on spelling errors
+          # so we restrict this to the docs folder
+          root: './docs'
+          # only warn for now
+          inline: warning # error
+          strict: false # true fails the build