Feature request: a VS Code extension version of Cindy

### Use case

Cindy is currently used mainly as a desktop app. For developers who spend most of their day inside VS Code, switching back and forth between the editor and the Cindy window breaks the flow — especially for quick questions about the code that is already open on screen.

### Current limitation

There is no way to use Cindy from inside VS Code. The editor and Cindy are two separate windows, and the code context (workspace, open files, current selection) has to be re-established by hand every time.

### Proposed solution

Ship a VS Code extension that brings Cindy's core capabilities into the editor:

- Chat with Cindy in a sidebar / panel, without leaving the editor
- Automatically pass editor context (workspace folder, open files, current selection) to Cindy
- Reuse the account, model and plugin (Ghost) configuration already set up in the desktop app, instead of configuring everything again
- Preview and apply Cindy's edits as a normal diff inside the editor

### Alternatives considered

- Keep using the desktop app side by side with VS Code — works, but the context switching and manual copy-paste of code is the main pain point this request is about.
- Use the existing terminal/CLI entry from VS Code's integrated terminal — closer, but it does not give editor-native context or diff review.

### Notes

I'm not sure whether this is already on the roadmap. If there is an existing plan or discussion, a pointer would be great. If the direction is acceptable, I'm happy to discuss the concrete shape — a standalone extension vs. a companion extension that talks to the running desktop app.

The issue names no existing files, tests, or entry points to start from. First clarify whether this should be a standalone VS Code extension or a companion to the desktop app, then define completion around editor chat, context sharing, configuration reuse, and diff-based edit review.

Written by the indexing model from the issue text.