fix(graphrag,mcp): drop premature 3-arg vectordb.Search call (RAN-37 CI)

The PR-27 build failed CI because internal/graphrag/clustering.go and
internal/mcp/tools.go both called the 3-arg vectordb.Index.Search(tenant,
query, k) signature, but that signature lives on RAN-20's vectordb
tenant-isolation work and is not yet on main. The 3-arg form leaked in
from a stacked branch during the original RAN-37 cut.

Restore the 2-arg Search(query, k) call in both sites and leave a
TODO(RAN-20) so the proper vector-side tenant scoping lands with the
RAN-20 follow-up. RAN-37's in-memory tenant invariants are unaffected:
SimilarErrors still narrows results by the per-tenant SignalStore's
EMITTED_BY edges, so cross-tenant hits cannot surface even while the
underlying vector index is shared.

go build / vet / test ./... and -race on graphrag + api all green.

Co-Authored-By: Paperclip <noreply@paperclip.ing>

Author: aksOps

internal/graphrag/clustering.go

@@ -9,8 +9,6 @@ import (
 	"context"
 	"fmt"
 	"time"
-
-	"github.com/RandomCodeSpace/otelcontext/internal/storage"
 )
 
 // clusterLog runs the log body through Drain and upserts a LogClusterNode
@@ -80,11 +78,14 @@ func (g *GraphRAG) SimilarErrors(ctx context.Context, clusterID string, k int) [
 	if query == "" && len(cluster.TemplateTokens) > 0 {
 		query = joinTokens(cluster.TemplateTokens)
 	}
-	// vectordb.Index.Search takes the tenant string directly; we resolve it
-	// from ctx via the same storage helper used by storesFor so both sides
-	// agree on coercion rules (empty → DefaultTenantID).
-	tenant := storage.TenantFromContext(ctx)
-	results := g.vectorIdx.Search(tenant, query, k*2) // over-fetch to filter
+	// TODO(RAN-20): vectordb.Index.Search itself is not yet tenant-scoped on
+	// `main`, so we call the 2-arg signature here. Tenant isolation for the
+	// SignalStore lookup above is already enforced via storesFor(ctx); the
+	// vector hits are then narrowed by the EmittedBy edges in this tenant's
+	// SignalStore on lines below, so cross-tenant hits cannot surface even
+	// while the underlying vector index is shared.
+	_ = ctx
+	results := g.vectorIdx.Search(query, k*2) // over-fetch to filter
 
 	// Map results back to log clusters.
 	seen := map[string]bool{clusterID: true}

internal/mcp/tools.go

@@ -590,8 +590,11 @@ func (s *Server) toolFindSimilarLogs(ctx context.Context, args map[string]any) T
 	if s.vectorIdx == nil {
 		return errorResult("vector index not yet initialized")
 	}
-	tenant := storage.TenantFromContext(mcpCtx(ctx))
-	results := s.vectorIdx.Search(tenant, query, limit)
+	// TODO(RAN-20): vectordb.Index.Search itself is not yet tenant-scoped on
+	// `main`. The tenant filter for log similarity will move into the
+	// vector index in the RAN-20 follow-up; until then this call is shared.
+	_ = ctx
+	results := s.vectorIdx.Search(query, limit)
 	data, err := json.MarshalIndent(results, "", "  ")
 	if err != nil {
 		return errorResult(fmt.Sprintf("failed to marshal similar logs: %v", err))