Add EditorWindow component with CodeMirror 6 using one-dark theme.
Detects language from file extension (js/ts/jsx/tsx, json, py, md)
via dynamic imports for code splitting. Features unsaved changes
indicator (yellow dot), Save button (TODO: SFTPService.WriteFile),
and Close button. Renders as an inline panel above the terminal.
File clicks in FileTree open the editor with mock content. Editor
re-creates when file path changes.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
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