feat(tui): Compact Mode Phase 1 - Display Hierarchy Implementation #9017

Summary

Implement Phase 1 of Compact Mode: 4-level display hierarchy for token efficiency and casual observer protection.

Background

Based on Trinitas Full Mode analysis (Hera, Athena, Artemis, Aurora, Muses), Compact Mode provides:

• Primary benefit: 60-80% token reduction
• Secondary benefit: Human-unreadable display (casual observer protection)

Phase 1 Scope (3 weeks)

Display Hierarchy Implementation

Deliverables

• Display level calculation logic (DisplayMode.getLevel())
• Shorthand notation generator (DisplayMode.toShorthand())
• Collapsed preview generator (DisplayMode.toCollapsed())
• Click-to-expand interaction
• Keyboard toggle (Ctrl+K or configurable)
• Mode indicator in TUI status bar
• User preference persistence

Technical Notes

• LLM Understanding Impact: None (Phase 1 is UI-only, API sends full text)
• Vendor Agnostic: ✅ Works with all LLM providers
• Performance: Minimal overhead, reactive rendering

Files to Modify

• packages/opencode/src/session/ - Add display-mode.ts
• packages/opencode/src/config/config.ts - Add displayMode config
• packages/opencode/src/cli/cmd/tui/routes/session/ - UI components

Success Criteria

• Toggle works correctly (on/off)
• All 4 display levels render appropriately
• Click-to-expand functions
• Settings persist across sessions

Related

• Phase 2: #TBD (Compression Engine)
• Phase 3: #TBD (Intelligence Layer)

Generated by Trinitas Full Mode Analysis