Maintenance: Recommendation Service - Improve exception handling safety (#109)

Co-authored-by: claude[bot] <41898282+claude[bot]@users.noreply.github.com>
Co-authored-by: Claude <[email protected]>

Author: 3 people

src/main/java/spring/memewikibe/application/RecommendationService.java

@@ -105,8 +105,8 @@ public List<MemeRecommendationResponse> searchWithReasons(String query, Long use
                 // 확장된 키워드 토큰들로 OR 조건 검색을 수행
                 log.info("Performing keyword search with OR conditions for tokens: {}", keywordTokens);
                 kwCandidates = memeRepository.findKeywordCandidatesAcrossFields(keywordTokens, of(useKwTopK));
-            } catch (Throwable t2) {
-                log.error("Custom keyword search failed, falling back to simple containing search.", t2);
+            } catch (Exception e) {
+                log.error("Custom keyword search failed, falling back to simple containing search.", e);
                 kwCandidates = memeRepository.findByTitleOrHashtagsContainingOrderByIdDesc(normKeywordQuery, of(useKwTopK));
             }
         }

src/main/java/spring/memewikibe/application/SafeFullTextSearchExecutor.java

@@ -26,7 +26,9 @@ public class SafeFullTextSearchExecutor {
     public List<Meme> tryFullText(String query, int limit) {
         try {
             return memeRepository.findCandidatesByFullTextSearch(query, limit);
-        } catch (Throwable ignored) {
+        } catch (Exception ignored) {
+            // Catch database-related exceptions (e.g., SQL syntax errors on H2)
+            // but let Error types (OutOfMemoryError, etc.) propagate
             return emptyList();
         }
     }