fix: match an inbound Message-ID with and without its RFC 5322 angle brackets in GetTaskByMessageID, since the outbound stamp always stores the bracketed form while an In-Reply-To header arrives either way depending on the replying client, so every reply whose brackets had been stripped missed its task, replied_at was never stamped, stop_on_reply stayed inert and a contact who had already answered kept receiving the rest of the sequence, and an empty header matched one of the 151 tasks carrying an empty message_id and linked the reply to an arbitrary campaign

internal/repository/pg_task.go

@@ -4,6 +4,7 @@ import (
 	"context"
 	"database/sql"
 	"errors"
+	"strings"
 	"time"
 
 	"github.com/google/uuid"
@@ -293,19 +294,24 @@ func (r *taskRepository) GetTask(ctx context.Context, taskID uuid.UUID) (*Task,
 	return task, err
 }
 
-// GetTaskByMessageID retrieves the latest task by RFC Message-ID.
+// GetTaskByMessageID retrieves the latest task by RFC Message-ID. Probes both
+// bracket forms: the stamp stores "<id@host>", an inbound In-Reply-To may not.
 func (r *taskRepository) GetTaskByMessageID(ctx context.Context, messageID string) (*Task, error) {
+	bare := strings.Trim(strings.TrimSpace(messageID), "<>")
+	if bare == "" {
+		return nil, nil
+	}
 	query := `
 		SELECT id, task_type, email_account_id, status, message_id,
 		       scheduled_at, completed_at, cloud_task_name, created_at, updated_at
 		FROM tasks
-		WHERE message_id = $1
+		WHERE message_id = $1 OR message_id = $2
 		ORDER BY created_at DESC
 		LIMIT 1
 	`
 
 	task := &Task{}
-	err := r.db.QueryRow(ctx, query, messageID).Scan(
+	err := r.db.QueryRow(ctx, query, bare, "<"+bare+">").Scan(
 		&task.ID,
 		&task.TaskType,
 		&task.EmailAccountID,

internal/repository/task_message_id_live_test.go

@@ -0,0 +1,101 @@
+package repository
+
+import (
+	"context"
+	"testing"
+
+	"github.com/google/uuid"
+)
+
+// The stamp stores "<id@host>" but an inbound In-Reply-To arrives either way,
+// and cleanMessageID strips the brackets before the lookup. Under the old exact
+// compare the bare-form case found nothing, so replied_at was never stamped and
+// stop_on_reply kept mailing a contact who had already answered.
+//
+//	WARMBLY_TEST_DB=postgres://warmbly:warmbly@localhost:15432/warmbly_dev?sslmode=disable \
+//	  go test ./internal/repository/ -run LiveTaskByMessageID -v
+func TestLiveTaskByMessageIDMatchesBracketedAndBareForms(t *testing.T) {
+	_, pool := liveContactDB(t)
+	ctx := context.Background()
+
+	org := uuid.New()
+	user := uuid.New()
+	account := uuid.New()
+	task := uuid.New()
+	bare := "regression-" + uuid.NewString() + "@example.test"
+	stored := "<" + bare + ">"
+
+	exec := func(sql string, args ...any) {
+		t.Helper()
+		if _, err := pool.Exec(ctx, sql, args...); err != nil {
+			t.Fatalf("setup %q: %v", sql, err)
+		}
+	}
+
+	// The user exists first: organizations.owner_user_id points at it.
+	exec(`INSERT INTO users (id, first_name, last_name, email)
+	      VALUES ($1, 'MsgID', 'Regression', $2)`,
+		user, "msgid-"+uuid.NewString()+"@example.test")
+	exec(`INSERT INTO organizations (id, name, owner_user_id)
+	      VALUES ($1, 'msgid regression', $2)`, org, user)
+	exec(`INSERT INTO email_accounts
+	        (id, user_id, organization_id, email, name, signature_plain, signature_html, provider)
+	      VALUES ($1, $2, $3, $4, 'MsgID Regression', '', '', 'smtp_imap')`,
+		account, user, org, "box-"+uuid.NewString()+"@example.test")
+	exec(`INSERT INTO tasks (id, task_type, email_account_id, status, message_id)
+	      VALUES ($1, 'campaign', $2, 'completed', $3)`, task, account, stored)
+
+	t.Cleanup(func() {
+		// Unwound in dependency order: tasks cascade from the mailbox, the
+		// mailbox and the org do not cascade from each other, and the org
+		// owns the user by foreign key, so the user goes last.
+		for _, stmt := range []struct {
+			sql string
+			arg any
+		}{
+			{`DELETE FROM email_accounts WHERE id = $1`, account},
+			{`DELETE FROM organizations WHERE id = $1`, org},
+			{`DELETE FROM users WHERE id = $1`, user},
+		} {
+			if _, err := pool.Exec(context.Background(), stmt.sql, stmt.arg); err != nil {
+				t.Errorf("cleanup %q: %v", stmt.sql, err)
+			}
+		}
+	})
+
+	repo := NewTaskRepository(pool)
+
+	for _, tc := range []struct {
+		name   string
+		lookup string
+	}{
+		{"bare form, as cleanMessageID hands it over", bare},
+		{"bracketed form, as the header carried it", stored},
+		{"bracketed with surrounding space", "  " + stored + "  "},
+	} {
+		t.Run(tc.name, func(t *testing.T) {
+			got, err := repo.GetTaskByMessageID(ctx, tc.lookup)
+			if err != nil {
+				t.Fatalf("lookup %q: %v", tc.lookup, err)
+			}
+			if got == nil {
+				t.Fatalf("lookup %q found no task; the reply would never link to its campaign", tc.lookup)
+			}
+			if got.ID != task {
+				t.Fatalf("lookup %q returned task %s, want %s", tc.lookup, got.ID, task)
+			}
+		})
+	}
+
+	t.Run("empty message id is not a wildcard", func(t *testing.T) {
+		for _, empty := range []string{"", "   ", "<>"} {
+			got, err := repo.GetTaskByMessageID(ctx, empty)
+			if err != nil {
+				t.Fatalf("lookup %q: %v", empty, err)
+			}
+			if got != nil {
+				t.Fatalf("lookup %q returned task %s; an absent header must match nothing", empty, got.ID)
+			}
+		}
+	})
+}