Feature request: Add OpenFile tool to open files in IDE editor without editing

Summary

Add an OpenFile (or RevealFile) tool that opens a file in the IDE editor for viewing, without requiring an edit operation.

Motivation

The Claude Code VSCode extension already surfaces files in the editor as a side effect of the Edit and Write tools (showing a diff for approval). However, there is no way to open a file for read-only viewing — the only way to trigger the IDE to show a file is to propose a change to it.

This creates an odd gap: Claude can read any file, but cannot show it to the user in their editor without fabricating an edit. A standalone OpenFile tool would close this gap naturally.

Proposed behavior

• OpenFile(file_path) — opens the file in the active IDE editor tab, read-only, no diff view
• Available in VSCode extension (and ideally JetBrains) environments
• When the IDE is not available (terminal), gracefully no-ops or falls back to printing the path

Example use case

User: "Can you open my settings file so I can review it?"
Claude: calls OpenFile("/Users/npantier/.claude/settings.json")
Result: file opens in editor tab

Currently this is impossible without making an unnecessary edit.