Phase P~S 전체 작업물: 검증 스크립트, 블록 템플릿, 설계 문서, 코드 수정

포함 내용:
- Phase P/Q/R/S 설계 문서 (IMPROVEMENT-PHASE-*.md)
- 영역별 검증 스크립트 (scripts/verify_*.py, test_*.py)
- 블록 템플릿 추가 (cards, emphasis 변형)
- 코드 수정: block_search, content_editor, design_director, slide_measurer
- catalog.yaml 블록 목록 업데이트
- CLAUDE.md, PROGRESS.md, README.md 업데이트

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

src/slide_measurer.py

@@ -217,6 +217,76 @@ def format_measurement_for_kei(
     return "\n".join(lines)
 
 
+def measure_candidate_block(html: str) -> dict[str, Any]:
+    """Phase P: 단일 후보 블록을 렌더링하여 높이 측정 + 스크린샷 캡처.
+
+    Args:
+        html: render_block_in_container()로 생성된 완전한 HTML
+
+    Returns:
+        {
+            "scrollHeight": 실제 콘텐츠 높이,
+            "containerHeight": 컨테이너 높이,
+            "overflowed": 넘침 여부,
+            "excess_px": 초과 px,
+            "screenshot_b64": base64 PNG 문자열
+        }
+    """
+    options = Options()
+    options.add_argument("--headless=new")
+    options.add_argument("--disable-gpu")
+    options.add_argument("--no-sandbox")
+    options.add_argument("--disable-dev-shm-usage")
+    options.add_argument("--force-device-scale-factor=1")
+    options.add_argument("--window-size=1400,900")
+
+    driver = None
+    try:
+        driver = webdriver.Chrome(options=options)
+
+        import urllib.parse
+        encoded = urllib.parse.quote(html)
+        driver.get(f"data:text/html;charset=utf-8,{encoded}")
+
+        try:
+            driver.execute_script("return document.fonts.ready")
+        except Exception:
+            pass
+
+        result = driver.execute_script("""
+            var container = document.querySelector('.candidate-container');
+            if (!container) return {error: 'container not found'};
+            return {
+                scrollHeight: container.scrollHeight,
+                containerHeight: parseInt(container.style.height) || container.clientHeight,
+                overflowed: container.scrollHeight > container.clientHeight + 2,
+                excess_px: Math.max(0, container.scrollHeight - container.clientHeight)
+            };
+        """)
+
+        if not result or "error" in result:
+            return {"scrollHeight": 0, "containerHeight": 0, "overflowed": False, "excess_px": 0, "screenshot_b64": None}
+
+        # 스크린샷 캡처
+        from selenium.webdriver.common.by import By
+        container = driver.find_element(By.CSS_SELECTOR, ".candidate-container")
+        screenshot_b64 = container.screenshot_as_base64
+
+        result["screenshot_b64"] = screenshot_b64
+        return result
+
+    except Exception as e:
+        logger.warning(f"[Phase P] 후보 블록 측정 실패: {e}")
+        return {"scrollHeight": 0, "containerHeight": 0, "overflowed": False, "excess_px": 0, "screenshot_b64": None}
+
+    finally:
+        if driver:
+            try:
+                driver.quit()
+            except Exception:
+                pass
+
+
 def capture_slide_screenshot(html: str) -> str | None:
     """Phase N-4: 렌더링된 슬라이드의 스크린샷을 base64 PNG로 캡처한다.