[BUG] IntelliJ IDEA: OpenClaudeInTerminalAction blocks EDT thread (453ms)

Preflight Checklist

• [x] I have searched existing issues and this hasn't been reported yet
• [x] This is a single bug report (please file separate reports for different bugs)
• [x] I am using the latest version of Claude Code

What's Wrong?

Summary

The Claude Code plugin for IntelliJ IDEA is blocking the Event Dispatch Thread (EDT) for 453ms when the "Open Claude in Terminal" action is triggered, causing performance warnings and potential UI freezes.

### Environment

• IntelliJ IDEA Version: 2025.2.4
• Claude Code Plugin Version: 0.1.12-beta
• Operating System: Windows 10
• Java Version: Java 25
• Claude Code CLI version is 2.0.46 (Windows Native)

### Description
When interacting with the "Open Claude in Terminal" button in the toolbar, IntelliJ IDEA reports that the OpenClaudeInTerminalAction is taking too long to execute on the EDT. The plugin needs to revise its AnAction.getActionUpdateThread property to specify whether the action should run on the EDT or a background thread.

### Expected Behavior
The action should complete without blocking the EDT, or it should be properly configured to run on a background thread.

What Should Happen?

### Actual Behavior
The action blocks the EDT for 453ms, triggering a performance warning in the logs and potentially causing UI freezes or stuttering.

### Impact

• UI responsiveness degradation when using the toolbar button
• Plugin exception warnings in the IDE logs
• Potential UX issues for users with slower systems

Error Messages/Logs

### Error Message from Logs
  2025-11-20 21:39:25,320 [  37950]   WARN - #c.i.o.a.i.ActionUpdater - 453 ms to call on EDT OpenClaudeInTerminalAction#presentation@MainToolbar
  (com.anthropic.code.plugin.actions.OpenClaudeInTerminalAction). Revise AnAction.getActionUpdateThread property [Plugin: com.anthropic.code.plugin]
  com.intellij.diagnostic.PluginException: 453 ms to call on EDT OpenClaudeInTerminalAction#presentation@MainToolbar (com.anthropic.code.plugin.actions.OpenClaudeInTerminalAction). Revise
  AnAction.getActionUpdateThread property [Plugin: com.anthropic.code.plugin]
        at com.intellij.diagnostic.PluginProblemReporterImpl.createPluginExceptionByClass(PluginProblemReporterImpl.java:23)
        at com.intellij.diagnostic.PluginException.createByClass(PluginException.java:90)
        at com.intellij.openapi.actionSystem.impl.ActionUpdaterKt.reportSlowEdtOperation(ActionUpdater.kt:700)
        at com.intellij.openapi.actionSystem.impl.ActionUpdaterKt.access$reportSlowEdtOperation(ActionUpdater.kt:1)
        at com.intellij.openapi.actionSystem.impl.ActionUpdater.computeOnEdt(ActionUpdater.kt:206)

  ### Location in IDE Logs
  File: `%APPDATA%\JetBrains\IntelliJIdea2025.2\log\idea.log`
  (This appears to be consistent across multiple session restarts)

Steps to Reproduce

### Steps to Reproduce

1. Open a project in IntelliJ IDEA 2025.2
2. Install the Claude Code [Beta] plugin (version 0.1.12-beta)
3. Click the "Open Claude in Terminal" button in the main toolbar
4. Check the IntelliJ IDEA logs

Claude Model

Sonnet (default)

Is this a regression?

I don't know

Last Working Version

_No response_

Claude Code Version

2.0.46

Platform

Anthropic API

Operating System

Windows

Terminal/Shell

PowerShell

Additional Information

### Suggested Fix
The OpenClaudeInTerminalAction class should:

1. Specify the appropriate getActionUpdateThread() implementation to indicate where the action should run (e.g., ActionUpdateThread.BGT for background thread if it performs I/O operations)
2. OR optimize the action to complete within the EDT's acceptable performance threshold
3. Consider offloading any blocking operations (file I/O, process spawning, etc.) to a background thread

### Additional Notes

• The plugin loads successfully and appears to function otherwise
• This is a beta version (0.1.12-beta), so performance optimization may still be in progress
• The issue manifests as a warning rather than a complete failure, but could impact user experience