autosave

[colin-i]

Summary

This PR introduces an experimental autosave mechanism intended to reduce data loss in case of application instability or crashes (observed on Raspberry Pi builds running Ubuntu-based source builds).

The system periodically exports open documents to temporary .ora autosave files and cleans them up on normal application exit.

Motivation

During testing on Raspberry Pi environments, I encountered occasional crashes leading to loss of unsaved work. This change is an initial mitigation step to improve recovery of work in progress.

Current Behavior

• Autosave runs at a configurable interval (autosave-interval)
• Only exports documents that are marked as modified (IsAutosaveDirty)
• Generates rotating autosave files per document
• Cleans up autosave files on normal application exit (StopAutosave)

Implementation Notes

• Extended Document with lightweight autosave tracking state
• Integrated autosave trigger into DocumentHistory
• Added periodic GLib-based autosave timer in WorkspaceManager
• Temporary .ora export files are written per document
• Basic rotation is supported via configurable file count
• Autosave state is reset after each successful export

Limitations / Known Issues

• This is an experimental system and may be refined further
• No recovery UI is included yet (manual file inspection required)
• File rotation logic is simple and may be improved
• Additional validation and edge cases may be addressed in follow-up commits

Future Work

• Investigate crash cases observed during testing (Raspberry Pi)
• Improve robustness of autosave triggering conditions
• Add recovery flow on application startup
• Potentially refine file rotation and storage strategy

Follow-up

I will continue investigating the crash scenario to identify whether there is a reproducible issue. Based on findings, I will return with additional fixes or refinements to both stability and autosave behavior.