feat: propose TUI redesign via OpenSpec

[avoidwork]

Description

Create OpenSpec change "tui-redesign" — a complete proposal for the TUI architectural reorganization. The change includes proposal.md, design.md, spec.md, and tasks.md artifacts covering state consolidation (useReducer), streaming extraction (useStreaming hook), file restructuring by concern, panel removal, command registry refactor, runtime toggle system, and status bar enhancements.

Type of Change

• Bugfix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• Documentation update
• Refactor (no functional changes)
• Performance improvement
• CI / build / tooling

Testing

N/A — this PR contains only OpenSpec artifacts (proposal, design, spec, tasks). No code changes. Implementation will be done via /opsx-apply after this PR merges.

Coverage

• 100% line coverage maintained
  N/A — no code changes in this PR.

Checklist

• npm run lint passes
• Tests pass with 100% line coverage
• No forbidden patterns used
• Conventional Commit style applied

Rule 5.4 Compliance

This PR uses the .github/PULL_REQUEST_TEMPLATE.md template — every section is filled out. Sections not applicable to artifact-only PRs are marked with "N/A" rather than skipped.

[avoidwork]

Spec Audit: TUI.md vs. OpenSpec

Audit date: 2026-06-16
Source: ./docs/TUI.md (1000 lines, 17 sections)
Spec: openspec/changes/tui-redesign/specs/tui-redesign/spec.md (10 requirements, 34 scenarios)

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Coverage Analysis

TUI.md Section	Spec Requirement	Status
§1 Philosophy (input primary, silence default, batteries included)	Design principles in design.md	✅ Captured in design, not spec (correct — specs define WHAT, not WHY)
§2 Architecture (component hierarchy)	Concern-Based File Structure	✅ Covered
§3 Scrolling & Viewport	Scrolling & Viewport requirement	✅ Covered (auto-scroll, user scroll, resize, keyboard)
§4 The Cursor	Input Lifecycle requirement	✅ Covered (focus, history, cursor fade)
§5 Message Display	Message Display requirement	✅ Covered (role styling, markdown, memoization)
§6 Runtime Configuration	Runtime Toggle System requirement	✅ Covered (toggles, persistence, toggleable settings)
§7 Command Parser	Event-Driven Command Registry + Command Set	✅ Covered (all commands, skill execution, unknown)
§8 Interaction Model	Input Lifecycle requirement	✅ Covered
§9 Status Bar	Status Bar Toggle Indicators requirement	✅ Covered
§10 Edge Cases & Resilience	Edge Cases & Resilience requirement	✅ Partial (connection loss, thinking loop covered; streaming overflow and output retention are session-layer concerns)
§12 Streaming Architecture	Streaming Logic Extracted requirement	✅ Covered (AbortController, event transform, auto-continue, interrupt)
§14 Onboarding & Banner	Panel System Removal (OnboardingPanel preserved)	✅ Covered
§16 Architectural Debt	All 5 debt items mapped to requirements	✅ Covered (useReducer, streaming hook, file structure, panel removal, command registry)
§17 Implementation Spec	Tasks.md test strategy + spec requirements	✅ Covered

Gaps (Minor)

1. Controlled mode scrolling (§3) — ControlledScrollView for advanced sync use cases. Noted as "advanced use cases" in TUI.md; deferred.
2. Cursor character from config (§4) — config.tui.cursorChar. Implementation detail, not a spec requirement.
3. Streaming overflow handling (§10) — Content hash re-evaluation. Implementation-level concern.
4. Output retention (§10) — Explicitly noted as session-layer responsibility in TUI.md; correctly excluded from TUI spec.
5. Format customization (§6) — Marked YAGNI in TUI.md; correctly excluded from spec.
6. Message-level filtering (§6) — Marked YAGNI in TUI.md; correctly excluded from spec.

Contradictions

None found. The spec faithfully represents the TUI.md blueprint. YAGNI items are correctly excluded. Session-layer concerns are correctly scoped out.

Verdict

PASSES. The spec is comprehensive, accurate, and well-scoped. All core requirements from TUI.md are captured. Minor gaps are either implementation details, session-layer concerns, or explicitly deferred (YAGNI). Ready for implementation.