perf(javascript): reuse graph buckets and query indexes

Append overlapping observations to node buckets instead of recopying groups, and share one node index across semantic seed admission and traversal. Preserve merged provenance and absent-seed behavior.

src/domain/javascript/javascriptSemanticQuery.ts

@@ -30,10 +30,6 @@ interface Traversal {
   readonly modules: Set<string>;
 }
 
-interface SeedAdmission {
-  readonly nodeIds: string[];
-}
-
 interface QueryResult {
   readonly retainedNodes: JavaScriptSemanticGraphNode[];
   readonly retainedRelations: JavaScriptSemanticGraphRelation[];
@@ -47,10 +43,10 @@ export const queryJavaScriptSemanticGraph = (
   const input = javaScriptSemanticQueryInputSchema.parse(rawInput);
   const queryId = queryIdentifier(graph, input);
   const seeds = resolveSeeds(graph, input);
-  const admission = admitSeeds(graph, seeds);
-  const retainedSeeds = admission.nodeIds;
+  const nodes = new Map(graph.nodes.map((node) => [node.node_id, node]));
+  const retainedSeeds = admitSeeds(nodes, seeds);
   const adjacency = buildAdjacency(graph.relations, input);
-  const traversal = traverse(graph, retainedSeeds, adjacency);
+  const traversal = traverse(nodes, retainedSeeds, adjacency);
   const result = createQueryResult(graph, traversal);
   const allRelevantUnknowns = relevantUnknownFrontiers(
     graph,
@@ -122,17 +118,16 @@ const createQueryResult = (
 };
 
 const admitSeeds = (
-  graph: JavaScriptSemanticGraph,
+  nodes: ReadonlyMap<string, JavaScriptSemanticGraphNode>,
   seeds: readonly string[],
-): SeedAdmission => {
-  const nodes = new Map(graph.nodes.map((node) => [node.node_id, node]));
+): string[] => {
   const retained: string[] = [];
   for (const nodeId of seeds) {
     const node = nodes.get(nodeId);
     if (node === undefined) continue;
     retained.push(nodeId);
   }
-  return { nodeIds: retained };
+  return retained;
 };
 
 const buildAdjacency = (
@@ -222,11 +217,10 @@ const addEntry = (
 };
 
 const traverse = (
-  graph: JavaScriptSemanticGraph,
+  nodes: ReadonlyMap<string, JavaScriptSemanticGraphNode>,
   seeds: readonly string[],
   adjacency: ReadonlyMap<string, TraversalEntry[]>,
 ): Traversal => {
-  const nodes = new Map(graph.nodes.map((node) => [node.node_id, node]));
   const nodeIds = new Set(seeds);
   const relationIds = new Set<string>();
   const functionIds = new Set<string>();