feat(webhooks): paginate list + call-history endpoints (server + web UI) (#1268)

Add total-count pagination to the webhook admin endpoints and the web UI.

Store:
- WebhookStore/WebhookCallStore gain Count; WebhookListFilter gains
  IncludeRevoked + Query (PG + SQLite, parameterized, tenant-scoped)

API:
- GET /v1/webhooks and GET /v1/webhooks/{id}/calls return
  {items, total, limit, offset} with server-side search + revoked filtering

Web UI:
- server-driven list pager + search/revoked filter; call-history dialog uses
  the real total (fixes the full-page "has more" boundary bug)
- i18n pager labels (en/vi/zh)

Tests: store pagination integration test; mock stores implement Count.
No schema migration (read-only COUNT).

internal/store/sqlitestore/webhook_calls.go

@@ -238,6 +238,31 @@ func (s *SQLiteWebhookCallStore) List(ctx context.Context, f store.WebhookCallLi
 	return out, rows.Err()
 }
 
+func (s *SQLiteWebhookCallStore) Count(ctx context.Context, f store.WebhookCallListFilter) (int, error) {
+	tid, err := requireTenantID(ctx)
+	if err != nil {
+		return 0, err
+	}
+
+	q := `SELECT COUNT(*) FROM webhook_calls WHERE tenant_id = ?`
+	args := []any{tid}
+
+	if f.WebhookID != nil {
+		q += ` AND webhook_id = ?`
+		args = append(args, *f.WebhookID)
+	}
+	if f.Status != "" {
+		q += ` AND status = ?`
+		args = append(args, f.Status)
+	}
+
+	var total int
+	if err := s.db.QueryRowContext(ctx, q, args...).Scan(&total); err != nil {
+		return 0, err
+	}
+	return total, nil
+}
+
 func (s *SQLiteWebhookCallStore) DeleteOlderThan(ctx context.Context, tenantID uuid.UUID, ts time.Time) (int64, error) {
 	var res sql.Result
 	var err error

internal/store/sqlitestore/webhooks.go

@@ -154,6 +154,13 @@ func (s *SQLiteWebhookStore) List(ctx context.Context, f store.WebhookListFilter
 		q += ` AND agent_id = ?`
 		args = append(args, *f.AgentID)
 	}
+	if !f.IncludeRevoked {
+		q += ` AND revoked = 0`
+	}
+	if f.Query != "" {
+		q += ` AND (name LIKE ? COLLATE NOCASE OR secret_prefix LIKE ?)`
+		args = append(args, "%"+f.Query+"%", f.Query+"%")
+	}
 	q += ` ORDER BY created_at DESC`
 
 	limit := f.Limit
@@ -180,6 +187,34 @@ func (s *SQLiteWebhookStore) List(ctx context.Context, f store.WebhookListFilter
 	return out, rows.Err()
 }
 
+func (s *SQLiteWebhookStore) Count(ctx context.Context, f store.WebhookListFilter) (int, error) {
+	tid, err := requireTenantID(ctx)
+	if err != nil {
+		return 0, err
+	}
+
+	q := `SELECT COUNT(*) FROM webhooks WHERE tenant_id = ?`
+	args := []any{tid}
+
+	if f.AgentID != nil {
+		q += ` AND agent_id = ?`
+		args = append(args, *f.AgentID)
+	}
+	if !f.IncludeRevoked {
+		q += ` AND revoked = 0`
+	}
+	if f.Query != "" {
+		q += ` AND (name LIKE ? COLLATE NOCASE OR secret_prefix LIKE ?)`
+		args = append(args, "%"+f.Query+"%", f.Query+"%")
+	}
+
+	var total int
+	if err := s.db.QueryRowContext(ctx, q, args...).Scan(&total); err != nil {
+		return 0, err
+	}
+	return total, nil
+}
+
 func (s *SQLiteWebhookStore) Update(ctx context.Context, id uuid.UUID, updates map[string]any) error {
 	tid, err := requireTenantID(ctx)
 	if err != nil {