refactor(diagrams): retire findContentHashForRouteByAgents

All production callers migrated to findLatestContentHashForAppRoute in
the preceding commits. The agent-scoped lookup adds no coverage beyond
the latest-per-(app,env,route) resolver, so the dead API is removed
along with its test coverage and unused imports.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

cameleer-server-app/src/main/java/com/cameleer/server/app/storage/ClickHouseDiagramStore.java

@@ -16,8 +16,6 @@ import java.security.MessageDigest;
 import java.security.NoSuchAlgorithmException;
 import java.sql.Timestamp;
 import java.time.Instant;
-import java.util.ArrayList;
-import java.util.Collections;
 import java.util.HashMap;
 import java.util.HexFormat;
 import java.util.List;
@@ -203,36 +201,6 @@ public class ClickHouseDiagramStore implements DiagramStore {
         return Optional.of(hash);
     }
 
-    @Override
-    public Optional<String> findContentHashForRouteByAgents(String routeId, List<String> agentIds) {
-        if (agentIds == null || agentIds.isEmpty()) {
-            return Optional.empty();
-        }
-
-        // Try cache first — return first hit
-        for (String agentId : agentIds) {
-            String cached = hashCache.get(cacheKey(routeId, agentId));
-            if (cached != null) {
-                return Optional.of(cached);
-            }
-        }
-
-        // Fall back to ClickHouse
-        String placeholders = String.join(", ", Collections.nCopies(agentIds.size(), "?"));
-        String sql = "SELECT content_hash FROM route_diagrams " +
-                "WHERE tenant_id = ? AND route_id = ? AND instance_id IN (" + placeholders + ") " +
-                "ORDER BY created_at DESC LIMIT 1";
-        var params = new ArrayList<Object>();
-        params.add(tenantId);
-        params.add(routeId);
-        params.addAll(agentIds);
-        List<Map<String, Object>> rows = jdbc.queryForList(sql, params.toArray());
-        if (rows.isEmpty()) {
-            return Optional.empty();
-        }
-        return Optional.of((String) rows.get(0).get("content_hash"));
-    }
-
     @Override
     public Optional<String> findLatestContentHashForAppRoute(String applicationId,
                                                              String routeId,

cameleer-server-app/src/test/java/com/cameleer/server/app/storage/ClickHouseDiagramStoreIT.java

@@ -154,24 +154,6 @@ class ClickHouseDiagramStoreIT {
         assertThat(retrieved.getDescription()).isEqualTo("v2");
     }
 
-    @Test
-    void findContentHashForRouteByAgents_returnsHash() {
-        RouteGraph graph = buildGraph("route-4", "node-z");
-        store.store(tagged("agent-10", "app-b", graph));
-        store.store(tagged("agent-20", "app-b", graph));
-
-        Optional<String> result = store.findContentHashForRouteByAgents(
-                "route-4", java.util.List.of("agent-10", "agent-20"));
-
-        assertThat(result).isPresent();
-    }
-
-    @Test
-    void findContentHashForRouteByAgents_emptyListReturnsEmpty() {
-        Optional<String> result = store.findContentHashForRouteByAgents("route-x", java.util.List.of());
-        assertThat(result).isEmpty();
-    }
-
     @Test
     void findProcessorRouteMapping_extractsMapping() {
         // Build a graph with 3 nodes: root + 2 children

cameleer-server-core/src/main/java/com/cameleer/server/core/storage/DiagramStore.java

@@ -3,7 +3,6 @@ package com.cameleer.server.core.storage;
 import com.cameleer.common.graph.RouteGraph;
 import com.cameleer.server.core.ingestion.TaggedDiagram;
 
-import java.util.List;
 import java.util.Map;
 import java.util.Optional;
 
@@ -15,16 +14,13 @@ public interface DiagramStore {
 
     Optional<String> findContentHashForRoute(String routeId, String instanceId);
 
-    Optional<String> findContentHashForRouteByAgents(String routeId, List<String> instanceIds);
-
     /**
      * Return the most recently stored {@code content_hash} for the given
      * {@code (applicationId, environment, routeId)} triple, regardless of the
      * agent instance that produced it.
      *
-     * <p>Unlike {@link #findContentHashForRoute(String, String)} and
+     * <p>Unlike {@link #findContentHashForRoute(String, String)}, this lookup
-     * {@link #findContentHashForRouteByAgents(String, List)}, this lookup is
+     * is independent of the agent registry — so it keeps working for routes
-     * independent of the agent registry — so it keeps working for routes
      * whose publishing agents have since been redeployed or removed.
      */
     Optional<String> findLatestContentHashForAppRoute(String applicationId,

cameleer-server-core/src/test/java/com/cameleer/server/core/ingestion/ChunkAccumulatorTest.java

@@ -22,7 +22,6 @@ class ChunkAccumulatorTest {
         public void store(com.cameleer.server.core.ingestion.TaggedDiagram d) {}
         public Optional<com.cameleer.common.graph.RouteGraph> findByContentHash(String h) { return Optional.empty(); }
         public Optional<String> findContentHashForRoute(String r, String a) { return Optional.empty(); }
-        public Optional<String> findContentHashForRouteByAgents(String r, List<String> a) { return Optional.empty(); }
         public Optional<String> findLatestContentHashForAppRoute(String app, String r, String env) { return Optional.empty(); }
         public Map<String, String> findProcessorRouteMapping(String app, String env) { return Map.of(); }
     };