feat(utas-host): serve GET /squad/active from Core

Migrate the active-squad READ off the Python oracle to the existing Core-backed projector, completing the squad authority (read + write + /squad/list + userMassInfo overlay) on one projector.

- classify: GET /ut/game/<t>/squad/active -> Route::SquadActive. Numeric GET /squad/<n> stays on Python (no Core multi-squad model yet).
- handle_squad_active returns the projector object via user_mass_info_squad(v, persona) — byte-identical to userMassInfo.squad; degrades to an empty overlay on stale/missing/Core-error, never falls back to Python.
- persona: new REQUIRED OPENFUT_PERSONA_ID (non-zero) on HostConfig, injected not baked, must match LSX/Blaze/POW/UTAS identity.
- tests: squad_active parity test; classify updated; README config table + A/B command.

fmt + clippy -D warnings + tests (24 host + adapter) green.

openfut-utas-host/src/main.rs

@@ -15,8 +15,8 @@ fn main() {
         }
     };
     eprintln!(
-        "utas-host starting: listen={} python_upstream={} core_url={} tables_dir={} catalog={} identity_store={}",
-        cfg.listen_addr, cfg.python_upstream, cfg.core_url, cfg.tables_dir, cfg.catalog_path, cfg.identity_store_path
+        "utas-host starting: listen={} python_upstream={} core_url={} tables_dir={} catalog={} identity_store={} persona_id={}",
+        cfg.listen_addr, cfg.python_upstream, cfg.core_url, cfg.tables_dir, cfg.catalog_path, cfg.identity_store_path, cfg.persona_id
     );
     let server = match Server::from_config(&cfg) {
         Ok(s) => s,