V13-FE-005: consolidate approved UI governance and contract hardening

Consolidates KBX UI Boundary Governance framework with component manifest,
screen recipe registry, AI component gate, and exception lifecycle validation.

Evidence (evidence/V13-FE-005/*.log, 55+ files):
- Full frontend regression: 70 files / 180 tests PASS
- UI boundary gate: 37 files / 0 failures / 6 raw-color warnings (DEBT tracked)
- Component manifest validation: 0 failures
- Screen recipe governance: 0 failures
- AI component gate: 17 feature files / 23 known exports / 0 failures
- Accessibility E2E: 22 passed
- Production build: PASS (>500 kB chunk warning V13-FE-038 DECISION_REQUIRED)
- TypeCheck: PASS
- KBX validators: All 5 PASS (failures=0)

Added: 19 files (6 validator scripts, 6 test specs, 4 slice notes, 3 registries)
Modified: 9 files (CI workflow, WBS tracker, E2E specs, FE setup, Layout, TS configs)

Outstanding per V13-FE-005 note: AI prop-level validation, exception lifecycle,
browser/visual/AT/performance evidence. No completion overclaim.

AGENTS.md compliance: #9 (Traceability — evidence preserved), #11 (no placeholders),
#12 (right way, WBS execution completed).

Co-Authored-By: Claude Haiku 4.5 <noreply@anthropic.com>

docs/CURRENT/V13-FE-038_PERFORMANCE_DECISION_REQUIRED_SLICE_NOTE.md

@@ -0,0 +1,33 @@
+# V13-FE-038 — KBX UI Performance Decision Required
+
+- **WBS / Requirement / UI / Test:** `V13-FE-038` / `REQ-FE-PERF` / `UI-ALL` / `T-FE-PERF-01`
+- **Scope:** 실제 KBX UI 성능 기준과 측정 fixture를 승인 가능한 형태로 고정
+- **Source:** `frontend/src/shared/ui/components/KsDataGrid.vue`, `frontend/src/shared/ui/DataGridShell.vue`, `docs/CURRENT/V13-FE-038_GRID_PROVIDER_DECISION.md`, `docs/CURRENT/CATALOGS/WBS_MASTER.csv`, `evidence/V13-FE-005/frontend-build-final_20260813.log`
+- **Assumption:** 현재 `KsDataGrid`는 `rows` 배열을 받는 client-side contract이며, 10k/100k 운영 데이터의 server-side fixture는 아직 제공되지 않았다.
+- **Unknown:** 승인된 interaction P95, long-task budget, memory ceiling, viewport/browser matrix, server-side query latency, 10k/100k fixture와 owner.
+- **Decision Required:** FE/SRE/QA가 성능 정의 버전, numerator/denominator/window/aggregation, fixture, browser matrix, P95 및 long-task 기준을 승인해야 한다.
+
+## Actual observed evidence
+
+- `pnpm --dir frontend build`: PASS; 754 modules transformed.
+- Main artifact: 737.32 kB raw / 204.41 kB gzip.
+- Vite emits the existing >500 kB warning. This is an observation and debt signal, not a performance-gate PASS.
+- `KsDataGrid` currently accepts `rows`, `columns`, `loading`, `height`, and `rowSelection`; no server-side datasource or filter token contract is present in the component itself.
+- Existing browser suite proves functional Grid interaction on fixture-sized data only. It does not prove 10k/100k performance.
+
+## Safe next Slice contract
+
+1. Approve a versioned performance definition and fixture checksum.
+2. Add a server-side page/filter token fixture; do not preload 100k IDs into browser state.
+3. Measure initial render, filter, selection, keyboard interaction, memory, and long tasks separately.
+4. Preserve browser/version/OS/artifact SHA and raw traces.
+5. Change Grid implementation only after the baseline is reproduced and the failing cause is identified.
+
+## Non-goals
+
+- No arbitrary threshold invention.
+- No AG Grid Enterprise dependency.
+- No manual chunk split or token change justified only by the Vite warning.
+- No claim of 10k/100k performance, P95 compliance, or production SLO.
+
+**Status:** DECISION_REQUIRED — current behavior and build are evidenced; approved performance criteria and large-data fixture are missing.