/careful hook triggers false positives on patterns inside commit messages

## Summary

The `/careful` hook uses string matching against the full bash command, including the contents of `git commit -m` arguments. This means commit messages that *describe* destructive commands (e.g., "this hook catches recursive deletes and database drops") trigger the safety warning even though no destructive command is being run.

## Steps to reproduce

1. Activate `/careful`
2. Run a commit whose message mentions a blocked pattern:

```bash
git add file.txt && git commit -m "feat: add guard for recursive delete and database drop patterns"
```

3. The hook fires on patterns found inside the quoted commit message string, not as an actual command.

## Expected behavior

The hook should only match destructive patterns in the executable portions of the command, not inside string arguments to `git commit -m`, `echo`, `printf`, or heredoc bodies.

## Suggested fix

Before pattern matching, split the command on shell operators (`&&`, `||`, `;`), then skip any segment that starts with `git commit`, `echo`, `cat`, or `printf` since those are producing text output, not executing destructive operations.

Found this while building a similar hook inspired by gstack's `/careful` approach. Happy to submit a PR if useful.

Start at the /careful hook entry point and reproduce the provided git commit command, then trace how the full bash command is split and matched. Done means destructive patterns in git commit -m, echo, printf, and heredoc text no longer trigger warnings, while patterns in executable command portions still do.

Written by the indexing model from the issue text.