shtab v1.8.0 stable

• ❓ fix bash error on optional nargs="?" (#184 <- #181)
• 🔀 fix zsh duplicate default remainder & swapped one_or_more/remainder (#200 <- #183, #198)
• 💅 misc minor docs updates (#202)
  • 🗒️ add own/example CLI file output (#192)
• 🛠️ misc framework updates (#203, #197, #193, #191)
  • 🐍 test support for Python 3.14