Verify TodoMVC

Read .agents/skills/e2e-dotnet/SKILL.md first. This skill only says what
is true of this app. The config is samples/TodoMvc/e2e.config.json (one
web target, todomvc); the tests are the NUnit classes in samples/TodoMvc
that derive from TodoMvcTest. The same steps hold for an xUnit v3 project
(topic writing-tests-xunit).

Launch

Nothing to start. The target's app.url is the hosted demo,
https://demo.playwright.dev/todomvc. Readiness is the page answering:
curl -sI https://demo.playwright.dev/todomvc returns 200. The app needs
no env, seeds, or database; the list lives in the browser's storage and
every test starts in a fresh browser context, so it starts empty. The real
model tests use the GitHub Copilot login (e2e login github-copilot).

Doctor

dotnet test --project samples/TodoMvc --filter "FullyQualifiedName~AddingTodosTests.Adds_a_single_todo"   # opens the app, adds a todo; exit 0

The sample has no model-free test, so its Doctor uses the model; a project
of your own should add a smoke test that needs none. APP_UNREACHABLE is the network or the demo being down. LOGIN_REQUIRED
or MODEL_PROVIDER_FAILED is the model login (topic debugging). A
LOCATOR_NOT_FOUND on the todo-item test id is the app itself. Run
Doctor first whenever anything looks off.

Drive

Live, over the registered e2e mcp server: open_session, then
observe, the verbs, and locate before writing any locator (topic
mcp). The catalog offers no credentials and no project tools. Scripted:
a class under samples/TodoMvc, Screen.GetByTestId("todo-item") for rows
(the footer filters are list items too), Agent.ActAsync for a flow that
varies. Every row has the same Toggle Todo checkbox and Delete button, so
name the row first: Todo("Task 2").GetByRole("button", "Delete").

Evidence

The proof is the dotnet test result: add --logger "trx;LogFileName=todomvc.trx" and keep the .trx file (topic running).
The port writes no report or trace page. A proof drives the page
the way a user does, the typed text, the checkbox, the footer filter, and
pins the action and the state after it: the row, the N items left
counter, the URL hash. Side effects: the list is the browser's local
storage (read with Browser.EvaluateAsync<string>); the server keeps
nothing. .e2e/cache holds the replay of each verified step; do not edit
it.

Bug bash

The bug bash fan-out is not ported, so a bash is a live MCP walk of a feature's
charter from features/, one H2 per feature, in the
slug|target|charter line format. A finding is a bug once a repro test
fails with ASSERTION_FAILED on the assertion that encodes it (topic
bug-bash). Give each repro its own data with Values.Unique(...). The
demo is hosted and shared, but the list is per browser context, so several
walks do not collide.

Cleanup

close_session stops the browser a session started. There is no app to
stop. Delete a repro test whose finding was rejected; keep the .trx
files and .e2e/cache, which are the proof.

Helpers

None. dotnet test and the e2e tool are the helpers.