Form names containing -> require shell quoting in extract mode

[harold]

Bug

When using cljdx extract with a form name that contains ->, the shell interprets > as a stdout redirect, silently sending output to a file instead of stdout.

Example

# Broken — shell interprets -> as redirect; cljdx receives "date-str-" as the form name
# and stdout goes to a file named "nice-date-str"
cljdx extract src/pf/webapp/util.cljs date-str->nice-date-str

# error: no form with id 'date-str-'

# Fixed — quoting prevents shell expansion
cljdx extract src/pf/webapp/util.cljs 'date-str->nice-date-str'

Impact

The failure mode is confusing: the error message says the form doesn't exist (because cljdx only receives the truncated date-str-), when in fact the form is present and correctly indexed. The cljdx index subcommand is unaffected since it only takes a filename argument.

Suggestion

• Document the quoting requirement in --help output and/or the README, e.g. "Form names containing -> or ! should be single-quoted to prevent shell interpretation."
• Optionally, detect when the supplied form id looks like a truncated symbol (no match but a match exists with a -> prefix) and emit a hint.