fix: Add smarttools and GUI dependencies as defaults

- Add smarttools dependency from git URL
- Make PyQt6 and QScintilla default dependencies (not optional)
  since artifact-editor is primarily a GUI application

This ensures `pip install artifact-editor` works out of the box
without needing to specify [gui] extra.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

pyproject.toml

@@ -28,6 +28,10 @@ classifiers = [
 ]
 dependencies = [
     "PyYAML>=6.0",
+    "smarttools @ git+https://gitea.brrd.tech/rob/SmartTools.git",
+    # GUI is required for the editor - include by default
+    "PyQt6>=6.4.0",
+    "QScintilla>=2.14.0",
 ]
 
 [project.optional-dependencies]