Add named appearance and export presets

Problem

CodeShot remembers one global appearance and export configuration. Users who create screenshots for different destinations, such as documentation, presentations, social posts, and transparent overlays, must repeatedly change several options when switching workflows.

Proposed solution

Add named presets that capture the complete appearance and export configuration and can be selected from the CodeShot toolbar.

Include a small set of built-in presets, for example:

• Documentation
• Social
• Transparent
• Minimal

Allow users to save the current configuration as a custom preset, rename or duplicate custom presets, and delete custom presets. When settings differ from the selected preset, indicate that the preset has unsaved changes, such as Social*.

Preset selection should reuse the existing options and preview update paths. Built-in presets should remain immutable but may be duplicated as custom presets.

Acceptance criteria

• The toolbar provides a preset selector.
• Selecting a preset immediately applies all included appearance and export settings to the preview.
• Users can create, rename, duplicate, and delete custom presets.
• Built-in presets cannot be overwritten or deleted.
• Modified settings are visibly distinguished from the last selected preset.
• Presets persist between Visual Studio sessions.
• Existing users retain their current settings after upgrading.
• Tool-window capture behavior remains unchanged for settings that do not apply to captured images.

Start by tracing the existing toolbar options and preview update paths in the Visual Studio extension. Design how built-in and custom presets store the complete appearance and export configuration, including persistence and upgrade compatibility. Done means the selector, custom preset operations, unsaved-change indicator, session persistence, and unchanged tool-window capture behavior meet the acceptance criteria.