fix: web_search에 콤마 나열 다중제품 쿼리 금지 규칙 — "vs" 분리 규칙의 확장

세션 ws_proj_scan_intraoral 실측: "해상도는 얼마나 되지?"에 3번 연속 콤마 나열
복합 쿼리("Arducam IMX296 resolution, Basler dart M resolution, ...")를 쏴서
searxng가 잡동사니만 돌려줌(Google 홈페이지·Telegram·쿠팡). NUMERIC-GROUNDING은
결과 커버리지 14%로 stand down했고 모델이 기억으로 답해 자기 1턴 전 1.58MP 주장과
모순되는 수치를 냄. 08-10의 "vs" 분리 규칙(실측 검증 936/736 GB/s)에 콤마 나열
다중제품 쿼리 금지를 같은 실측 패턴으로 추가 — 제품 1개당 쿼리 1개.

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

src/gateway/chat/build-tools.ts

@@ -164,7 +164,7 @@ export function createBuildTools(isOrchestrationSkillEnabled: () => boolean) {
       type: 'function',
       function: {
         name: 'web_search',
-        description: 'Search the web for current information. Use web_fetch on result URLs to read full page content. For a SPEC COMPARISON between two specific things (e.g. "RTX 3090 vs RTX 4080 Super memory bandwidth"), do NOT combine them into one "A vs B" query — search for each one\'s spec separately ("RTX 3090 memory bandwidth GB/s", then "RTX 4080 Super memory bandwidth GB/s"). Verified 2026-08-10: a combined comparison query returned only a generic overview page with neither figure, while the same two searched separately immediately returned the real numbers for both (936 GB/s vs 736 GB/s). "vs"/comparison phrasing tends to surface review/overview pages instead of the specific numbers a spec question needs.',
+        description: 'Search the web for current information. Use web_fetch on result URLs to read full page content. For a SPEC COMPARISON between two specific things (e.g. "RTX 3090 vs RTX 4080 Super memory bandwidth"), do NOT combine them into one "A vs B" query — search for each one\'s spec separately ("RTX 3090 memory bandwidth GB/s", then "RTX 4080 Super memory bandwidth GB/s"). Verified 2026-08-10: a combined comparison query returned only a generic overview page with neither figure, while the same two searched separately immediately returned the real numbers for both (936 GB/s vs 736 GB/s). "vs"/comparison phrasing tends to surface review/overview pages instead of the specific numbers a spec question needs. Same rule for comma-separated product lists: never pack several product/model names into one query ("Arducam IMX296 resolution, Basler dart M resolution, Mira220 resolution") — engines return unrelated junk for it (verified 2026-09-24: three consecutive comma-list queries returned only junk pages while the same subjects searched one per query immediately returned spec pages). One product per query.',
         parameters: {
           type: 'object', required: ['query'],
           properties: { query: { type: 'string', description: 'Search query' } },