Fix #4946: Improve error handling in file editing tools

[roomote]

• Enhanced error handling in writeToFileTool, applyDiffTool, searchAndReplaceTool, and insertContentTool
• Added comprehensive try-catch blocks around DiffViewProvider operations
• Improved error reporting and logging for better debugging
• Fixed silent failures by ensuring handleError is called for all tool errors
• Enhanced DiffViewProvider.open() method with better error validation
• Added proper cleanup and state reset on errors
• All tests now passing including previously failing writeToFileTool error handling tests

This resolves the issue where file editing tools were failing silently on Ubuntu 22.04 with Claude 4.0 Sonnet via OpenRouter.

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Important

Improves error handling in file editing tools by adding try-catch blocks, enhancing error reporting, and ensuring proper cleanup, resolving silent failures on Ubuntu 22.04.

• Error Handling:
  • Added try-catch blocks in writeToFileTool, applyDiffTool, searchAndReplaceTool, and insertContentTool to handle errors during file operations.
  • Enhanced error logging and reporting in presentAssistantMessage.ts for better debugging.
  • Ensured handleError is called for all tool errors to prevent silent failures.
• DiffViewProvider:
  • Improved DiffViewProvider.open() with better error validation and handling.
  • Added proper cleanup and state reset on errors in DiffViewProvider.ts.
• Testing:
  • All tests now passing, including previously failing writeToFileTool error handling tests.

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[daniel-lxs]

The issue should be solved by #4980