* feat(extensions): add inline-bash example for expanding !{command} in prompts
Adds an example extension that expands inline bash commands within user
prompts before sending to the agent. Uses the `input` event to transform
patterns like `!{pwd}` or `!{git status}` into their output.
Preserves existing `!command` whole-line bash behavior.
* docs(extensions): add inline-bash to README
* chore: fix stupid bug
