Reorganize documentation structure for messages and development topics

[oblomov-dev]

Summary

This PR restructures the documentation to improve organization and navigation by splitting content into more granular sections and reorganizing the sidebar navigation hierarchy.

Key Changes

• Split Messages/Errors documentation: Separated error handling into a dedicated errors.md file while keeping general messaging in messages.md
• Reorganized sidebar navigation:
  • Converted "Messages, Errors" from a single link to a collapsible section with subsections (Messages, Errors, Logging)
  • Converted "View" section to collapsible with "Definition" as the main page
  • Converted "Model" section to collapsible with "Binding" as the main page
  • Moved "File Handling" to a collapsible section with "XLSX" as a subsection
  • Added "Soft Keyboard" as a new top-level item under "Specific" features
• Renamed documentation files for clarity:
  • model/model.md → model/binding.md (better reflects content)
  • development/view.md → view/definition.md (moved to subdirectory)
  • development/trouble.md → specific/soft_keyboard.md (repurposed and relocated)
• Cleaned up sidebar: Removed "Troubleshooting" as a top-level item and consolidated "Logging" and "XLSX" under their respective feature categories

Notable Details

• Error handling content was extracted from the general messages documentation to provide dedicated, focused guidance on exception handling patterns
• The navigation structure now better reflects the logical grouping of related topics
• File handling features are now organized hierarchically with XLSX as a specific implementation example

https://claude.ai/code/session_011bPsgLdQNom3MjbrsVYGUV