* fix(examples): keep the extension example's tests passing as the contract grows
The README's package-test commands failed one test on main:
isinstance(registry, ExtensionRegistry) is False because the test's
FakeRegistry does not implement knowledge_provider(), which
extension-api 0.2.7 added to the runtime-checkable protocol. The same
assertion broke earlier when plugin() was added. Nothing in CI runs
these tests, so each addition to the contract broke them silently.
FakeRegistry now records knowledge_provider() and plugin() calls, and
the test asserts the example registers neither, as its README says.
Extension Package Check, which already runs when the contract changes,
now installs each bundled example that has a tests/ directory next to
the checkout's extension-api and runs the README's pytest and ruff
commands. A backend test pins that step and checks that every tested
example declares those tools in its dev extra.
The example README and the extensions guide now count nine
contribution kinds, including knowledge providers.
* docs(changelog): reference #7364 for the extension example test fix
* test(extensions): name the missing package-test step in the wiring pin
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Co-authored-by: Willem Jiang <willem.jiang@gmail.com>
