Update default mount point to $HOME/remote-rssh for consistency, and introduce backtunnel-auth-setup script for restricted SFTP-only key management. Update docs, scripts, and uninstall/install logic to reflect changes. Ensure robust handling of user-specified mount points in backtunnel-access.

scripts/uninstall.sh

@@ -38,6 +38,7 @@ say "Uninstalling from PREFIX=${PREFIX} DESTDIR=${DESTDIR} (PURGE=${PURGE})"
 # --- Remove binaries ---
 rm -f "$BINDIR/backtunnel-share" \
       "$BINDIR/backtunnel-access" \
+      "$BINDIR/backtunnel-auth-setup" \
       "$BINDIR/backtunnel-share-gui" \
       "$BINDIR/backtunnel-access-gui" \
       "$BINDIR/backtunnel-open-term" \