Open-label, Non-randomized, Multi-cohort, Phase 1b/2 Trial Investigating the Safety, Tolerability, and Antitumor Activity of STC-15 (a METTL3 Inhibitor) as a Part of Combination Therapy With Toripalimab in Participants With Selected Advanced Cancers and as Monotherapy in Participants With Selected Sarcomas | Arctuva