Surface common tracker pattern link across APIs

Expose the existing tracker_patterns.common_tracker_pattern_id foreign
key on the TrackerPattern type so it is possible to tell whether a
pattern is linked to the global common-tracker catalog (its description
likely came from the seed or the mapping/enrichment agents) or has no
link (added manually or inherited). This is a read-only debugging aid
for agent-generated descriptions; no migration or write path changes.

The field is added in sync across all four API surfaces (GraphQL, MCP,
CLI, n8n) plus the console UI, and covered by e2e assertions for both
the linked and unlinked cases.

Signed-off-by: Émile Ré <emile@probo.com>

e2e/console/tracker_pattern_test.go

@@ -15,12 +15,16 @@
 package console_test
 
 import (
+	"context"
 	"testing"
+	"time"
 
 	"github.com/stretchr/testify/assert"
 	"github.com/stretchr/testify/require"
 	"go.probo.inc/probo/e2e/internal/factory"
 	"go.probo.inc/probo/e2e/internal/testutil"
+	"go.probo.inc/probo/pkg/coredata"
+	"go.probo.inc/probo/pkg/gid"
 )
 
 func TestTrackerPattern_Create(t *testing.T) {
@@ -45,6 +49,7 @@ func TestTrackerPattern_Create(t *testing.T) {
 							displayName
 							maxAgeSeconds
 							description
+							commonTrackerPatternId
 							createdAt
 							updatedAt
 						}
@@ -60,15 +65,16 @@ func TestTrackerPattern_Create(t *testing.T) {
 			CreateTrackerPattern struct {
 				TrackerPatternEdge struct {
 					Node struct {
-						ID            string `json:"id"`
-						Pattern       string `json:"pattern"`
-						MatchType     string `json:"matchType"`
-						TrackerType   string `json:"trackerType"`
-						DisplayName   string `json:"displayName"`
-						MaxAgeSeconds *int   `json:"maxAgeSeconds"`
-						Description   string `json:"description"`
-						CreatedAt     string `json:"createdAt"`
-						UpdatedAt     string `json:"updatedAt"`
+						ID                     string  `json:"id"`
+						Pattern                string  `json:"pattern"`
+						MatchType              string  `json:"matchType"`
+						TrackerType            string  `json:"trackerType"`
+						DisplayName            string  `json:"displayName"`
+						MaxAgeSeconds          *int    `json:"maxAgeSeconds"`
+						Description            string  `json:"description"`
+						CommonTrackerPatternID *string `json:"commonTrackerPatternId"`
+						CreatedAt              string  `json:"createdAt"`
+						UpdatedAt              string  `json:"updatedAt"`
 					} `json:"node"`
 				} `json:"trackerPatternEdge"`
 				CookieBanner struct {
@@ -101,6 +107,7 @@ func TestTrackerPattern_Create(t *testing.T) {
 		require.NotNil(t, node.MaxAgeSeconds)
 		assert.Equal(t, maxAge, *node.MaxAgeSeconds)
 		assert.Equal(t, "Google Analytics tracking cookie", node.Description)
+		assert.Nil(t, node.CommonTrackerPatternID, "a manually created pattern is not linked to the common catalog")
 		assert.Equal(t, bannerID, result.CreateTrackerPattern.CookieBanner.ID)
 	})
 
@@ -607,6 +614,93 @@ func TestTrackerPattern_List(t *testing.T) {
 	})
 }
 
+func TestTrackerPattern_CommonTrackerPatternID(t *testing.T) {
+	t.Parallel()
+
+	t.Run("reflects the common catalog link", func(t *testing.T) {
+		t.Parallel()
+		owner := testutil.NewClient(t, testutil.RoleOwner)
+
+		bannerID := factory.CreateCookieBanner(owner)
+		categoryID := factory.CreateCookieCategory(owner, bannerID)
+		patternID := factory.CreateTrackerPattern(owner, categoryID)
+
+		const query = `
+			query($id: ID!) {
+				node(id: $id) {
+					... on TrackerPattern {
+						id
+						commonTrackerPatternId
+					}
+				}
+			}
+		`
+
+		var result struct {
+			Node struct {
+				ID                     string  `json:"id"`
+				CommonTrackerPatternID *string `json:"commonTrackerPatternId"`
+			} `json:"node"`
+		}
+
+		require.NoError(t, owner.Execute(query, map[string]any{"id": patternID}, &result))
+		assert.Nil(t, result.Node.CommonTrackerPatternID, "a freshly created pattern has no catalog link")
+
+		commonID := seedCommonTrackerPattern(t)
+		linkTrackerPatternToCommon(t, patternID, commonID)
+
+		require.NoError(t, owner.Execute(query, map[string]any{"id": patternID}, &result))
+		require.NotNil(t, result.Node.CommonTrackerPatternID, "the catalog link must surface once set")
+		assert.Equal(t, commonID.String(), *result.Node.CommonTrackerPatternID)
+	})
+}
+
+func seedCommonTrackerPattern(t *testing.T) gid.GID {
+	t.Helper()
+
+	ctx := context.Background()
+	conn := dialTestPg(t, ctx)
+	t.Cleanup(func() { _ = conn.Close(ctx) })
+
+	id := gid.New(gid.NilTenant, coredata.CommonTrackerPatternEntityType)
+	now := time.Now().UTC()
+
+	_, err := conn.Exec(ctx, `
+		INSERT INTO common_tracker_patterns (
+			id, tracker_type, pattern, match_type, description, confidence, created_at, updated_at
+		) VALUES (
+			$1, $2, $3, $4, $5, $6, $7, $8
+		)
+	`, id, "COOKIE", "e2e_common_"+id.String(), "EXACT", "Seeded catalog description", 1.0, now, now)
+	require.NoError(t, err)
+
+	t.Cleanup(func() {
+		cleanupCtx, cancel := context.WithTimeout(context.Background(), 5*time.Second)
+		defer cancel()
+
+		cleanupConn := dialTestPg(t, cleanupCtx)
+		defer func() { _ = cleanupConn.Close(cleanupCtx) }()
+
+		_, err := cleanupConn.Exec(cleanupCtx, `DELETE FROM common_tracker_patterns WHERE id = $1`, id)
+		assert.NoError(t, err, "cleanup: cannot delete seeded common tracker pattern %s", id)
+	})
+
+	return id
+}
+
+func linkTrackerPatternToCommon(t *testing.T, patternID string, commonID gid.GID) {
+	t.Helper()
+
+	ctx := context.Background()
+	conn := dialTestPg(t, ctx)
+	t.Cleanup(func() { _ = conn.Close(ctx) })
+
+	_, err := conn.Exec(ctx, `
+		UPDATE tracker_patterns SET common_tracker_pattern_id = $1 WHERE id = $2
+	`, commonID, patternID)
+	require.NoError(t, err)
+}
+
 func TestTrackerPattern_RBAC(t *testing.T) {
 	t.Parallel()