Optimize diff view rendering

[bennekrouf]

What changed

• Optimized the diff view rendering by precomputing and caching the syntax highlighting of diffs.
• Introduced a new RenderedFile struct to store pre-rendered diff files.
• Updated the DiffView component to use the pre-rendered diffs.
• Improved the drive function in workspace.rs to handle approvals more efficiently and reduce unnecessary polling.
• Enhanced the commit function in flow.rs to handle paths to stage more accurately and avoid unnecessary operations.
• Refactored the status function in git.rs to use git status --porcelain -z for better handling of file paths.
• Added tests for the new rendering logic and other changes.

Why

• The previous diff rendering approach was inefficient, re-parsing and highlighting the entire diff on every render, leading to performance issues, especially with large diffs.
• The new approach reduces the computational load by parsing and highlighting the diff only once and reusing the result.
• Improvements in the drive function and commit function enhance the responsiveness and efficiency of the application.

How to test

• Open the diff view for a large file or a repository with multiple changes.
• Observe that the rendering is smooth and does not lag.
• Navigate to the workspace screen and trigger a commit.
• Verify that the commit process is efficient and does not involve unnecessary operations.
• Check the status of a repository with special characters in file names to ensure proper handling.