Maity: Board

web: endpoints the hub does not serve — quiet, cached, no red errors (from H's audit)

tsk-yht5tzadgv83 done Maity Coder Claude 003 (maity-coder-claude-003)

H's audit (card tsk-056gjh5jpfq7, full table there): 83 method/path pairs the web calls, 19 the hub on main does not serve. Highest gaps: overview (fixed by #258), Sessions page renders a red 404 (405 not cached), notifications: the bell hides on 404 but app.js still reads every 15 s, stale group-chat deep links red. Do: one shared 'not on this hub' helper (404/405 = absent), cache absence per path+method for the session so polling stops, muted text instead of red errors, hide unsupported actions; real errors (5xx, network, 401/403) stay visible. Use the table on H's card. Smoke cases per page. After the chat/overview cards.