No supported way to open a file in a GUI app on the user's behalf (open -e fails with procNotFound)

**Summary**

Attempting `open -e file.txt` (or `open -t`) to hand the user a local file in their default text editor / TextEdit fails with `procNotFound: no eligible process with specified descriptor`, regardless of sandbox state. This looks like a genuine capability gap rather than a permission to grant — the Bash tool's subprocess appears to have no route into the user's actual logged-in GUI/desktop session at all, so any `open`-style "launch an app for the user" command is a dead end.

**Impact**

Minor but recurring: there's no way for an agent to say "I've opened this for you to look at" for a native file the way it can hand over a file via other mechanisms. The closest alternative delivers a file to the user but doesn't open a specific native app with it.

**Reproduction**

1. In a Claude Code session on macOS, run `open -e `.
2. Observe `procNotFound: no eligible process with specified descriptor` (or equivalent), independent of `dangerouslyDisableSandbox`.

**Suggested fix**

Either document this explicitly as unsupported (so agents stop attempting it and burning a turn on it), or provide a supported mechanism for handing a file to the user's default or chosen application.

Start by reproducing in a Claude Code session on macOS with `open -e ` and noting the `procNotFound` failure. The issue names no files or tests and leaves the fix open between documentation and a new supported mechanism, so done means maintainers first decide which direction is wanted and the resulting behavior or docs make this unsupported path explicit.

Written by the indexing model from the issue text.