fix(node,client): survive a transient hub state on login, and surface a failed node-key link

Two defensive gaps turned a routine reset-and-reonboard into "impossible de
démarrer le node":

1. daemon._login_with_retry retried a 401 (node key not linked yet) but `raise`d
   on every other status, so a 429 — the daemon's own 5s retries hitting the
   sign-in rate limit — or a 502/503 while the hub restarts during a deploy
   killed the process, and systemd crash-looped it. Those statuses (429, 5xx)
   are now retried with a back-off that respects Retry-After, so a freshly
   reset node stays alive (the operator needs it up to read its key) instead of
   dying. A genuine 4xx (400/422) still raises.

2. create-group's linkNodeKey swallowed every error as "already linked or same
   key" — but PUT /me/node_key is idempotent and returns 200 on a re-link, so
   there was no benign error to hide: the catch only ever hid a real failure
   (a rejected session, a bad key), letting the wizard proceed against a node
   that looked linked but was not, which then could not authenticate. The link
   failure now surfaces (detectNode shows it).

test_login_retry_is_resilient.py holds the retry behaviour (429/5xx retried,
Retry-After honoured, 401 stays alive, 400 still raises); red before, green
after. common/node/hub suites green.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

1 files changed, 9 insertions, 5 deletions

diff --git a/packages/meshbay-hub/src/meshbay_hub/static/create-group-page.js b/packages/meshbay-hub/src/meshbay_hub/static/create-group-page.js
index f81247d..85fe53c 100644
--- a/packages/meshbay-hub/src/meshbay_hub/static/create-group-page.js
+++ b/packages/meshbay-hub/src/meshbay_hub/static/create-group-page.js
@@ -142,11 +142,15 @@ function CreateGroupWizard({ token, username, onCreated, allowPublicGroups = tru
 
   const linkNodeKey = useCallback(async (pk) => {
     if (!pk) return;
-    try {
-      await hubFetch('/v1/users/me/node_key', {
-        method: 'PUT', token, body: { pk_node_ed25519: pk },
-      });
-    } catch { /* already linked or same key */ }
+    // `PUT /me/node_key` is idempotent — linking the same key again returns 200,
+    // so there is no "already linked" case to swallow here. A failure means the
+    // hub did not record this node's key (a rejected session, a malformed key),
+    // and the node then fails to authenticate and never comes up. It must
+    // surface — `detectNode`'s catch shows it — rather than let the wizard
+    // proceed against a node that looks linked but is not.
+    await hubFetch('/v1/users/me/node_key', {
+      method: 'PUT', token, body: { pk_node_ed25519: pk },
+    });
   }, [token]);
 
   const detectNode = useCallback(async () => {