feat: T1016 dns_config probe + server-side drift detection + Crucible DNS DRIFT badge

server/internal/db/builds_test.go

@@ -3,6 +3,7 @@ package db
 import (
 	"database/sql"
 	"errors"
+	"strings"
 	"testing"
 	"time"
 
@@ -92,6 +93,24 @@ func TestSetPinnedBuild(t *testing.T) {
 	}
 }
 
+func TestSetPinnedBuildUnknownID(t *testing.T) {
+	d := openTestDB(t)
+	now := time.Now()
+	insertBuild(t, d, &models.BuildRecord{ID: "b1", WorkerName: "w", ServerURL: "u", Wallet: "w", CreatedAt: now, Pinned: true})
+
+	err := d.SetPinnedBuild("missing")
+	if err == nil {
+		t.Fatal("expected error for unknown build id")
+	}
+	if !strings.Contains(err.Error(), "not found") {
+		t.Fatalf("unexpected error: %v", err)
+	}
+	b1, _ := d.GetBuild("b1")
+	if b1.Pinned {
+		t.Fatal("unknown id should leave builds unpinned, not keep prior pin")
+	}
+}
+
 func TestGetLatestBuildForPlatform(t *testing.T) {
 	d := openTestDB(t)
 	base := time.Now().UTC().Truncate(time.Second)

server/internal/db/sqlite.go

@@ -307,7 +307,8 @@ func (d *Database) GetLatestBuildForPlatform(platform string) (*models.BuildReco
 }
 
 // SetPinnedBuild unpins all builds then pins the one with the given id.
-// If id is empty, all builds are unpinned.
+// If id is empty, all builds are unpinned. Returns an error when id is
+// non-empty but no build row matches (avoids leaving all builds unpinned).
 func (d *Database) SetPinnedBuild(id string) error {
 	_, err := d.Exec(`UPDATE builds SET pinned = 0`)
 	if err != nil {
@@ -316,8 +317,18 @@ func (d *Database) SetPinnedBuild(id string) error {
 	if id == "" {
 		return nil
 	}
-	_, err = d.Exec(`UPDATE builds SET pinned = 1 WHERE id = ?`, id)
-	return err
+	res, err := d.Exec(`UPDATE builds SET pinned = 1 WHERE id = ?`, id)
+	if err != nil {
+		return err
+	}
+	n, err := res.RowsAffected()
+	if err != nil {
+		return err
+	}
+	if n == 0 {
+		return fmt.Errorf("build not found: %s", id)
+	}
+	return nil
 }
 
 func (d *Database) ListBuilds(limit int) ([]*models.BuildRecord, error) {