feat(hub): one account, several linked nodes

An account links up to MAX_NODES_PER_ACCOUNT node keys (node_keys table)
instead of the one users.pk_node_ed25519; the migration carries each
account's key over and the downgrade keeps the last one linked.
/v1/nodes/auth accepts any linked key, and its token names the key that
won it (nk). PUT /me/node_key adds a key, idempotently, 409 past the
limit; DELETE /me/node_key names the key: a browser session any of its
own, a node only its own. Unlinking a key closes that node's socket and
refuses its tokens at once, on REST and on the socket; the account's other
nodes are untouched. /pubkeys no longer gives a node key to other accounts,
and gives the caller its last linked one, which installed desktop apps read.

The node reports waiting_for_node_key while its key is unlinked and signs
in again as soon as the hub says so, so a key linked again is back within
seconds; unlinking itself signs in first to hold a token naming its key.

Profile -> Linked nodes lists each node (connected, last seen, IP, linked
since, This machine in the desktop app) with Copy and Unlink, and adds a
key by hand. The Node page banner, Create group and the desktop app add
this machine's key instead of replacing another's. Messages that pointed
at Settings -> Link Node point at Profile -> Linked nodes.

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

1 files changed, 2 insertions, 2 deletions

diff --git a/packages/meshbay-hub/tests/test_sidebar_node_section.py b/packages/meshbay-hub/tests/test_sidebar_node_section.py
index 57c9e9e..c8e44ca 100644
--- a/packages/meshbay-hub/tests/test_sidebar_node_section.py
+++ b/packages/meshbay-hub/tests/test_sidebar_node_section.py
@@ -44,7 +44,7 @@ def test_the_wizard_says_so_after_each_way_it_links_one():
 
 def test_one_failed_read_does_not_hide_the_section_for_good():
     refresh = _body(APP, "const refreshNodeKey = useCallback(", "}, [user]);")
-    assert "/pubkeys" in refresh
+    assert "linkedNodeKeys(user.token)" in refresh
     assert not re.search(r"\.catch\(\(\)\s*=>\s*\{\s*\}\)", refresh), (
         "a swallowed failure leaves hasNodeKey false until a reload")
     assert "setTimeout(" in refresh, "a failed read is tried again"
@@ -53,4 +53,4 @@ def test_one_failed_read_does_not_hide_the_section_for_good():
 
 
 def test_the_session_effect_uses_the_same_read():
-    assert APP.count("/pubkeys`") == 1, "one place decides hasNodeKey"
+    assert APP.count("linkedNodeKeys(") == 1, "one place decides hasNodeKey"