onlook fix: auto-refresh web preview after saving files in Code panel

Resolves issue #2071

Description

This PR fixes a bug where changes made in the Code panel were not automatically applied to the web preview after saving. Users had to manually refresh the preview to see their code changes, which disrupted the development workflow.

Changes made:

Added refreshPreviewAfterSave() method to IDEManager that automatically reloads the web preview after successful file saves
Added shouldRefreshPreview() method to only refresh for web-relevant file types (.js, .jsx, .ts, .tsx, .css, .scss, .sass, .less, .html)
Implemented a 100ms delay to ensure file write operations complete before triggering the preview reload
Enhanced code formatting and added proper error handling

The fix ensures that when users save code changes in the Code panel, they immediately see the results in the web preview, creating a smooth development experience as intended.

Related Issues

Fixes #2071

Type of Change

[x] Bug fix
[ ] New feature
[ ] Documentation update
[ ] Release
[ ] Refactor
[ ] Other (please describe):

Testing

To test this fix:

Open a project in Onlook
Navigate to the Code panel (Dev tab) in the right panel
Open any web-relevant file (.js, .tsx, .css, etc.)
Make visible changes to the code (e.g., modify styles, add text, change colors)
Save the file using Ctrl+S (Cmd+S on Mac) or the Save button
Expected behavior: The web preview should automatically refresh within ~100ms and display the changes
Previous behavior: Changes would not appear until manual refresh

Edge cases tested:

Saving non-web files (.md, .json, etc.) should not trigger unnecessary refreshes
Multiple rapid saves should work correctly
Sandbox disconnection should not cause errors

Screenshots (if applicable)

https://github.com/user-attachments/assets/d26679d7-6d26-4a93-816e-025f1bd65bd3

Additional Notes

The solution only affects manual saves from the Code panel, avoiding interference with other code-writing workflows (AI code application, undo/redo, etc.)
File type checking prevents unnecessary reloads for non-web files

[!IMPORTANT] Adds auto-refresh functionality to web preview after saving web-relevant files in IDEManager.

Behavior:

Adds refreshPreviewAfterSave() to IDEManager to auto-refresh web preview after saving files.

Introduces shouldRefreshPreview() to check if file types affect the preview (e.g., .js, .css).

Implements a 100ms delay to ensure file write completion before refresh.

Edge Cases:

Non-web files (e.g., .md, .json) do not trigger refresh.

Handles multiple rapid saves and sandbox disconnection without errors.

Misc:

Enhanced error handling and code formatting in index.ts.

^{This description was created by}^{for 3b925d842f04802ef520d7c98668029199bb4848. You can customize this summary. It will automatically update as commits are pushed.}