Is your feature request related to a problem?

Currently, eko stores snapshots and allows history viewing, but users must manually inspect diffs to understand what changed between snapshots. This slows down understanding of project evolution, especially in large codebases.

Describe the solution you'd like

Introduce AI-generated summaries for each snapshot, automatically describing what changed in human-readable form.

When a snapshot is created (eko save):

1. Generate diff between current and previous snapshot
2. Convert diff into structured format (added / deleted / modified files)
3. Send structured diff to AI model
4. Receive short summary (1–2 lines)
5. Store summary in snapshot metadata (SQLite)
6. Display summary in eko history

Example Output
[124] Added JWT authentication module and updated login flow
[125] Refactored database connection layer for performance improvements
[126] Fixed null pointer bug in file parser

Suggested Data Model Update
Add to snapshots table:
ai_summary TEXT,
ai_model TEXT,
summary_generated_at DATETIME

CLI Impact

Before
eko history
→ shows only snapshot IDs + timestamps

After
eko history
→ shows only snapshot IDs + timestamps

Describe alternatives you've considered

• Tagging system (feature / bugfix / refactor)
• Risk level detection (low / medium / high)
• Detailed explanation mode (eko explain )
• Offline LLM support

Additional Context

No response