The Oxford comma, always, the one-line description included

Every list of three or more takes the serial comma: the one-liner in
pyproject.toml, meshterm/__init__.py, and --help ("USB, Bluetooth, or TCP",
"Windows, macOS, and Linux"), the README, the changelog, the manuals, the
issue and PR templates, and six strings the app shows (the region-name
rule, a repeater setting's help, the diagnostics tool's description, and
the archive confirms). The Windows-console notice is rewrapped so its
comma keeps it inside 72 columns.

Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>

.github/ISSUE_TEMPLATE/bug.yml

@@ -94,7 +94,7 @@ body:
       description: >
         Only if you are running on something the diagnostics file cannot name. It knows a
         PicoCalc from a regular terminal, but a uConsole and a laptop look much the same to
-        it. Leave blank on a desktop, laptop or Mac.
+        it. Leave blank on a desktop, laptop, or Mac.
       placeholder: "ClockworkPi uConsole (CM4)"
 
   - type: input

.github/PULL_REQUEST_TEMPLATE.md

@@ -13,6 +13,6 @@
 - [ ] I've read [CONTRIBUTING.md](../blob/main/CONTRIBUTING.md) and agree its licensing terms apply to this contribution
 - [ ] `python -m pytest -q` passes, including the dual-platform gallery gate
 - [ ] `ruff check .` and `ruff format --check .` are clean
-- [ ] New screens, rows and hints go through the helpers in `ui/menus.py`, and follow the
+- [ ] New screens, rows, and hints go through the helpers in `ui/menus.py`, and follow the
       lexicon and UX standards in `CLAUDE.md`
 - [ ] Anything user-visible has a line in `CHANGELOG.md` under `[Unreleased]`

.github/workflows/ci.yml

@@ -3,7 +3,7 @@
 # Split in two on purpose. Style is a property of the source, not of the machine, so
 # `lint` runs once and its failure is unambiguous. Behaviour is a property of the
 # machine, so `test` runs everywhere we claim to work — the description promises
-# Windows, macOS and Linux, and until this file existed that promise had only ever been
+# Windows, macOS, and Linux, and until this file existed that promise had only ever been
 # checked on one of them.
 name: CI