• Use /help <question> to ask for help about using aider, customizing settings,
  troubleshooting, using LLMs, etc.
• Allow multiple use of /undo.
• All config/env/yml/json files now load from home, git root, cwd and named command line switch.
• New $HOME/.aider/caches dir for app-wide expendable caches.
• Default --model-settings-file is now .aider.model.settings.yml.
• Default --model-metadata-file is now .aider.model.metadata.json.
• Bugfix affecting launch with --no-git.