startServer() returns plain object, not Promise — use startGateway() for programmatic async use

Gateway startup traps: (1) startServer() returns { stop, port, hosts } synchronously — use startGateway() from cli/start.ts for Promise<GatewayHandle>. (2) loadConfig() in config.ts is SYNC — calling .then() throws TypeError. (3) EADDRINUSE fires as async 'error' event — wrap server.listen() in a Promise. (4) Use port 0 (ephemeral) in tests. (5) In-process callers MUST pass local:true — hosted mode disables FS ops in @loreai/core (breaks getGitRemote(), .lore.md import, config loading). (6) lore run and lore import always set opts.local=true.