fix(hub): a username is unique whatever its case

Registration refuses a name that differs from an existing one only by case;
accounts that already do keep their names, and a pending retry needs the exact
name (F-26).

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

1 files changed, 24 insertions, 0 deletions

diff --git a/packages/meshbay-hub/tests/test_username_case.py b/packages/meshbay-hub/tests/test_username_case.py
new file mode 100644
index 0000000..42f4815
--- /dev/null
+++ b/packages/meshbay-hub/tests/test_username_case.py
@@ -0,0 +1,24 @@
+"""
+A username is unique whatever its case.
+
+Invitations and member management name people by username, so "Alice" beside
+"alice" is one person to whoever reads the list — and a second account under
+the other spelling is the way to be mistaken for them.
+"""
+
+import pytest
+from test_bundle_pepper import KEY
+
+
+async def _register(client, username, email):
+    return await client.post("/v1/users/register", json={
+        "username": username, "auth_key": KEY, "email": email})
+
+
+@pytest.mark.asyncio
+async def test_a_name_differing_only_by_case_is_taken(client):
+    assert (await _register(client, "alice_case", "a1@example.invalid")).status_code == 201
+    for other in ("Alice_case", "ALICE_CASE", "alice_CASE"):
+        r = await _register(client, other, "a2@example.invalid")
+        assert r.status_code == 409, (other, r.text)
+