By Andrew Goudsward WASHINGTON (Reuters) – Donald Trump is readying what may be his best shot at avoiding spending much of next year in a courtroom facing criminal charges of trying to overturn his 2020 election defeat, kicking off an appeal that could go to the Supreme Court. The gambit by the former U.S. president and frontrunner for the 2024 Republican nomination may succeed, legal experts said — not necessarily by persuading higher courts of the merits of his case, but simply by bogging down the system and keeping him free to campaign against Democratic President Joe Biden. Trump’s lawyer…