70eb3fc13f
Migrate GET /hub from the Python proxy to a Rust handler deriving counts from authoritative state: clubPlayers = owned PLAYER cards in Core (consumables/staff excluded via catalog kind; may be lower than Python's profile count by the deferred Legend instances = DIFFERENT-BY-DESIGN), auction/tradePile counts from the durable market store via the async bridge. Fail-closed 503 on Core error; market read failure degrades cosmetic counts to 0. Adds classify arm, handler, ownership + integration tests; reachability tool marks hub migrated.