docs: show optional make params in README; tighten Makefile sync rule

- import-off: show limit/batch/min-scans params in make command examples
- CLAUDE.md: clarify that parameter changes to make targets also require README update

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

CLAUDE.md

@@ -100,7 +100,7 @@ update the README if the change affects any of the following:
 - **Stack or dependencies** — new or removed libraries
 - **Environment variables** — new, renamed, or removed variables
 - **API endpoints** — new routes, changed paths or methods, removed endpoints
-- **Makefile targets** — new or removed `make` commands
+- **Makefile targets** — new, removed, or changed `make` commands (including parameters)
 - **Project structure** — new top-level packages under `cmd/`, `internal/domain/`,
   `internal/adapters/`, or `internal/infra/`
 - **Database schema** — new tables added to the high-level table list

backend/README.md

@@ -116,7 +116,7 @@ make run-worker-free   # Воркер free-очереди
 | `make migrate-down` | Откатить последнюю миграцию |
 | `make migrate-status` | Статус миграций |
 | `make migrate-create name=<name>` | Создать новую миграцию |
-| `make import-off file=<path>` | Импортировать каталог из OpenFoodFacts JSONL/GZ |
+| `make import-off file=<path> [limit=N] [batch=N] [min-scans=N]` | Импортировать каталог из OpenFoodFacts JSONL/GZ |
 
 ## Импорт каталога продуктов
 
@@ -128,11 +128,13 @@ make run-worker-free   # Воркер free-очереди
 
 # Через make (DSN берётся из .env)
 make import-off file=openfoodfacts-products.jsonl.gz
+make import-off file=openfoodfacts-products.jsonl.gz limit=10000 min-scans=0
 
-# Или напрямую с дополнительными флагами
+# Или напрямую
 go run ./cmd/importoff \
   -file=openfoodfacts-products.jsonl.gz \
   -dsn="$DATABASE_URL" \
+  -limit=10000 \
   -min-scans=1
 ```