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, 7 insertions, 1 deletions

diff --git a/packages/meshbay-hub/tests/test_node_ws_auth.py b/packages/meshbay-hub/tests/test_node_ws_auth.py
index 7d96851..ca2cb25 100644
--- a/packages/meshbay-hub/tests/test_node_ws_auth.py
+++ b/packages/meshbay-hub/tests/test_node_ws_auth.py
@@ -44,6 +44,11 @@ async def _make_user(client, username: str) -> dict:
 
 
 async def _announce_node(client, user: dict) -> str:
+    # A node only ever reaches the socket with its key linked to the account:
+    # `/v1/nodes/auth` issues no token otherwise.
+    r = await client.put("/v1/users/me/node_key", json={"pk_node_ed25519": user["pk_ed"]},
+                         headers={"Authorization": f"Bearer {user['token']}"})
+    assert r.status_code == 200, r.text
     # Announce now requires proof of possession of the node key (M8).
     import time as _t
     ts = int(_t.time())
@@ -62,8 +67,9 @@ async def _announce_node(client, user: dict) -> str:
 
 
 def _node_token(user: dict) -> str:
+    """What `/v1/nodes/auth` issues: a node token naming the key that signed in."""
     from meshbay_hub.auth import issue_access_token
-    return issue_access_token(user["user_id"], scope="node")
+    return issue_access_token(user["user_id"], scope="node", node_key=user["pk_ed"])
 
 
 @pytest.mark.asyncio