refactor: rename binary from quoteforge to qfs

- Rename cmd/server to cmd/qfs for shorter binary name
- Update all documentation references (README, CLAUDE.md, etc.)
- Update build commands to output bin/qfs
- Binary name now matches directory name

Usage:
  go run ./cmd/qfs              # Development
  go build -o bin/qfs ./cmd/qfs # Production

Co-Authored-By: Claude Sonnet 4.5 <noreply@anthropic.com>

MIGRATION_PRICE_REFRESH.md

@@ -89,7 +89,7 @@ mysql -u user -p RFQ_LOG < migrations/004_add_price_updated_at.sql
 - `internal/models/configuration.go` - добавлено поле `PriceUpdatedAt`
 - `internal/services/configuration.go` - добавлен метод `RefreshPrices()`
 - `internal/handlers/configuration.go` - добавлен обработчик `RefreshPrices()`
-- `cmd/server/main.go` - добавлен маршрут `/api/configs/:uuid/refresh-prices`
+- `cmd/qfs/main.go` - добавлен маршрут `/api/configs/:uuid/refresh-prices`
 - `web/templates/index.html` - добавлена кнопка и JavaScript функции
 - `migrations/004_add_price_updated_at.sql` - SQL миграция
 - `CLAUDE.md` - обновлена документация