Remove automatic session resume suggestion on startup

- Remove the interactive prompt that asked users to resume in-progress sessions
- Remove unused new_session parameter from run_interactive()
- Remove unused info_inline() function from G3Status
- Explicit --resume <session_id> flag still works

crates/g3-cli/src/accumulative.rs

@@ -306,7 +306,6 @@ async fn handle_command(
                 cli.show_code,
                 chat_combined_content,
                 workspace_dir,
-                cli.new_session,
                 None, // agent_name (not in agent mode)
                 None, // initial_project (not supported in accumulative mode yet)
             )