feat(rag): modularize knowledge retrieval pipeline

src/test/java/com/superbiz/agent/service/ToolInvocationRecorderTest.java

@@ -2,7 +2,10 @@ package com.superbiz.agent.service;
 
 import com.fasterxml.jackson.databind.ObjectMapper;
 import com.superbiz.agent.domain.entity.ToolInvocation;
+import com.superbiz.agent.dto.ContextPack;
 import com.superbiz.agent.dto.EvidenceBlock;
+import com.superbiz.agent.dto.KnowledgeQuery;
+import com.superbiz.agent.dto.RetrievalTrace;
 import com.superbiz.agent.repository.ToolInvocationRepository;
 import com.superbiz.agent.util.SessionContextHolder;
 import org.junit.jupiter.api.Test;
@@ -129,23 +132,51 @@ class ToolInvocationRecorderTest {
                 .evidenceCandidateCount(3)
                 .evidenceBlockCount(1)
                 .evidenceBlocks(List.of(block))
+                .contextPack(ContextPack.builder()
+                        .packedText("packed evidence")
+                        .strategy("ranked_evidence_char_budget")
+                        .charBudget(4000)
+                        .usedChars(15)
+                        .includedSources(List.of("doc.md"))
+                        .omittedSources(List.of())
+                        .build())
+                .retrievalTrace(RetrievalTrace.builder()
+                        .originalQuery("query")
+                        .rewrittenQuery("query")
+                        .selectedAttempt("UNFILTERED_VECTOR")
+                        .evidenceStatus(ToolInvocationRecorder.EVIDENCE_STATUS_SUPPORTED)
+                        .attempts(List.of(RetrievalTrace.Attempt.builder()
+                                .name("UNFILTERED_VECTOR")
+                                .candidateCount(3)
+                                .topScore(0.42)
+                                .topSimilarity(0.79)
+                                .usable(true)
+                                .build()))
+                        .build())
+                .build();
+        KnowledgeQuery query = KnowledgeQuery.builder()
+                .originalQuery("query")
+                .rewrittenQuery("query")
+                .domainHints(List.of())
+                .matchedKeywords(List.of())
+                .entities(List.of())
+                .l0Titles(List.of())
+                .l0MatchCount(0)
                 .build();
 
         ToolInvocationRecorder.LookupKnowledgeRecord record = ToolInvocationRecorder.LookupKnowledgeRecord.from(
-                "query",
-                KnowledgeIndexService.L0Hint.empty(),
-                List.of(),
-                false,
+                query,
                 result,
                 null,
                 null,
-                10,
-                -1
+                10
         );
 
         assertEquals(3, record.evidenceCandidateCount());
         assertEquals(1, record.evidenceBlockCount());
         assertEquals(1, record.evidenceBlocks().size());
         assertTrue(String.valueOf(record.evidenceBlocks().get(0).get("content_preview")).endsWith("..."));
+        assertEquals("UNFILTERED_VECTOR", record.retrievalLayer());
+        assertEquals(3, record.l1MatchCount());
     }
 }