[UI] Implement bilingual themed prototype shell

[yutthaphon]

Problem

The shell, stage, cue list, timeline, and inspector must switch System/Light/Dark and English/Thai without losing state.

Change

Complete the bounded work for this issue without importing later milestone scope.

Behavior

Before: The required capability, decision, or evidence is incomplete.
After: The named outcome is reviewable and satisfies its linked specification and milestone gates.

Acceptance

• Dependencies and stable IDs are linked.
• Observable acceptance evidence is recorded.
• Security, compatibility, recovery, Windows, EN/TH, theme, and accessibility impacts are handled where applicable.
• No local Plan/ file is uploaded.

[yutthaphon]

VID-IMPL-P00-006 Implementation Progress: C4 Evidence Audit Complete

Status: Partial Evidence Substantiated (AC-SHELL-01..06 & VID-TERM-014 PASS; AC-SHELL-07 & External Tool Blocked)

Substantiated Acceptance Criteria (PASS)

• AC-SHELL-01 (Workspace Navigation): 5 routes navigable with viewmodel state preservation ✅
• AC-SHELL-02 (Theme Switching): Light/Dark/System switching ≤500ms; media stage #0B0B0B invariant ✅
• AC-SHELL-03 (31-Key Bilingual Parity): Complete en-US/th-TH catalog parity; fallback hierarchy; named formatting ✅
• AC-SHELL-04 (Thai Typography & IME): Line height ≥1.35× (actual ~1.85×); TSF IME keystroke isolation ✅
• AC-SHELL-05 (Accessibility & Contrast): Text contrast (Light 14.47:1, Dark 15.93:1 ≥4.5:1); Focus 10.28:1 ≥3:1; High Contrast themes verified; UIA landmarks verified ✅
• AC-SHELL-06 (Performance & Motion): P95 UI pacing ≤16.7ms; 0ms reduced motion ✅
• VID-TERM-014 (Terminology Consistency): 18 frozen glossary terms verified consistent ✅

Evidence Path: .agents/reviews/P00/haiku-vid-impl-p00-006-executed-evidence-review-c4.md

Blocked External Gates (CAPTURE_BLOCKED_EXTERNAL)

• AC-SHELL-07 (Screenshot Manifest): Interactive desktop capture unavailable on headless WIN11-X64-BASE environment (GDI CopyFromScreen invalid window station handle; WinUI 3 REGDB_E_CLASSNOTREG due to missing WinAppSDK COM registration). Fabricated 1×1 pixel stubs and false 1920×1080 dimensional claims have been invalidated and permanently deleted. Truthful CAPTURE_BLOCKED_EXTERNAL status with 24-item target matrix (workspace/locale/theme/density/scale/resolution metadata) and null SHA-256 values recorded.
• Accessibility Insights CLI: Not installed on execution environment; internal automated accessibility tests (contrast, UIA landmarks, High Contrast themes) executed independently and verified PASS.

Fabrication Remediation

C3 independent review (2026-08-03 18:00 UTC) identified fabricated evidence: 24 screenshot files were 1×1 pixel PNG stubs with false 1920×1080 dimensional claims and identical SHA-256 hashes. Immediate remediation: all invalid stubs deleted; screenshot-manifest.json corrected to truthful CAPTURE_BLOCKED_EXTERNAL status with honest environmental disclosure.

Issue Status

• Current: OPEN (implementation complete for 6 verifiable AC gates + supporting evidence)
• Pending: Interactive screenshot capture re-execution if WIN11-X64-BASE becomes interactive (Session-0→User session; WinAppSDK COM registration restored)
• Not Claiming: Full validation; external tooling availability; screenshot visual correctness

Next Step

Awaiting coordinator decision on partial acceptance scope (6 verifiable AC gates) vs. full acceptance blocking (AC-SHELL-07 screenshot manifest gated on environment). Issue remains open pending either re-execution authorization or partial-acceptance decision.

Authority: Phase-00 Validation Evidence Review C4 (Haiku, Quality Governance Reviewer)
Audit Date: 2026-08-03
Substantiation Method: Read-only code inspection, unit test execution, accessible artifact verification; no source mutations, no network operations.

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