fix(node): an invitation the hub never registered is a code nobody can use

`create_invite` wrote the invite to the roster and *then* asked for the
hub. An unreachable hub therefore raised "Hub not connected" after the
code was already stored: the operator saw an error and no code, and a
valid invitation sat in the roster that nobody had been given. Every
retry left another.

Registering first means a failure costs nothing — no code exists to be
orphaned. A membership row without an invite is harmless: without the
code there is still no group key. The endpoint is idempotent (`if not
mem: db.add(...)`, no 409), so the SPA registering the same membership
again right after createInvite costs nothing either.

The registration is now fatal rather than swallowed, which is the part
that matters. `/v1/groups/mine` joins GroupMember, so someone who was
never registered does not see the group at all and can never redeem the
code. Tolerating that failure handed the operator a code that cannot
work and said nothing — a worse outcome than the error, because it is
silent. Skipped only when there is no username to register with: the MNP
path allows an empty one and there the SPA is the one that registers.

Found by test_invite_then_join_delivers_the_gek, whose fixture had no
hub and which passed only because the failure was swallowed. It has one
now. And 0443cf8 added this registration to the CLI path without any
test asserting it happened, which is how it came to be skipped whenever
the hub was merely absent — test_cli_invite_asks_the_hub_for_an_account_
never_a_key checks it now, and
test_an_unreachable_hub_leaves_no_invite_behind covers the orphan
(verified failing against the previous ordering).

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01AbwJDbNTkiRUh7HTWEoyss

0 files changed, 0 insertions, 0 deletions