Add codespell support (config, workflow to detect/not fix) and make it fix few typos

.codespellrc

@@ -0,0 +1,6 @@
+[codespell]
+# Ref: https://github.com/codespell-project/codespell#using-a-config-file
+skip = .git*,.codespellrc
+check-hidden = true
+# ignore-regex = 
+# ignore-words-list =

.github/workflows/codespell.yml

@@ -0,0 +1,25 @@
+# Codespell configuration is within .codespellrc
+---
+name: Codespell
+
+on:
+  push:
+    branches: [main]
+  pull_request:
+    branches: [main]
+
+permissions:
+  contents: read
+
+jobs:
+  codespell:
+    name: Check for spelling errors
+    runs-on: ubuntu-latest
+
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4
+      - name: Annotate locations with typos
+        uses: codespell-project/codespell-problem-matcher@v1
+      - name: Codespell
+        uses: codespell-project/actions-codespell@v2

changelog.md

@@ -11,7 +11,7 @@
 ## 0.0.332 - 2025-10-01
 
 - Switched to using per-subscription Copilot API endpoints in accordance with [GitHub's docs](https://docs.github.com/en/copilot/how-tos/administer-copilot/manage-for-enterprise/manage-access/manage-network-access) (fixes https://github.com/github/copilot-cli/issues/76)
-- Fixed a bug where `/user [list | show | swtich]` did not include users signed in from all authentication modes (fixes https://github.com/github/copilot-cli/issues/58)
+- Fixed a bug where `/user [list | show | switch]` did not include users signed in from all authentication modes (fixes https://github.com/github/copilot-cli/issues/58)
 - Fixed a bug where switching to another user with `/user switch` did not take effect in the GitHub MCP server
 - Improved the screenreader experience by disabling the scrollbar in the `@` file picker, the `--resume` session picker, and the `/` command picker
 - Improved the polish of the scrollbar container (increased the width, reduced the opacity of the gutter)