Pi 0.50.1

Fixed

• Git extension updates now handle force-pushed remotes gracefully instead of failing (#961 by @aliou)
• Extension ctx.newSession({ setup }) now properly syncs agent state and renders messages after setup callback runs (#968)
• Fixed extension UI bindings not initializing when starting with no extensions, which broke UI methods after /reload
• Fixed /hotkeys output to title-case extension hotkeys (#969 by @Perlence)
• Fixed model catalog generation to exclude deprecated OpenCode Zen models (#970 by @DanielTatarkin)
• Fixed git extension removal to prune empty directories