feat(import): add CoreHub pricing collector and importer

- coreshub_pricing_lib.go: CoreHub pricing data extraction and parsing
- import_coreshub_pricing.go: importer with dry_run support
- import_coreshub_pricing_test.go: unit tests for importer
- coreshub_pricing_sample.txt: test fixture

scripts/import_coreshub_pricing.go

@@ -0,0 +1,88 @@
+//go:build llm_script
+
+package main
+
+import (
+	"database/sql"
+	"flag"
+	"fmt"
+	"io"
+	"net/http"
+	"os"
+	"time"
+)
+
+type coreshubPricingImportConfig struct {
+	URL     string
+	Fixture string
+	DryRun  bool
+	Timeout time.Duration
+}
+
+func main() {
+	loadSubscriptionImportEnv()
+
+	var url string
+	var fixture string
+	var dryRun bool
+	var timeoutSeconds int
+
+	flag.StringVar(&url, "url", defaultCoresHubPricingURL, "CoresHub 官方价格页")
+	flag.StringVar(&fixture, "fixture", "", "CoresHub 价格样例文件")
+	flag.BoolVar(&dryRun, "dry-run", false, "仅解析并打印摘要，不写入数据库")
+	flag.IntVar(&timeoutSeconds, "timeout", 20, "请求超时（秒）")
+	flag.Parse()
+
+	cfg := coreshubPricingImportConfig{
+		URL:     url,
+		Fixture: fixture,
+		DryRun:  dryRun,
+		Timeout: time.Duration(timeoutSeconds) * time.Second,
+	}
+
+	var db *sql.DB
+	var err error
+	if !cfg.DryRun {
+		db, err = subscriptionImportDB()
+		if err != nil {
+			fmt.Fprintf(os.Stderr, "open db: %v\n", err)
+			os.Exit(1)
+		}
+		defer db.Close()
+	}
+
+	if err := runCoresHubPricingImport(cfg, db, os.Stdout); err != nil {
+		fmt.Fprintf(os.Stderr, "import_coreshub_pricing: %v\n", err)
+		os.Exit(1)
+	}
+}
+
+func runCoresHubPricingImport(cfg coreshubPricingImportConfig, db *sql.DB, out io.Writer) error {
+	client := &http.Client{Timeout: cfg.Timeout}
+	raw, err := fetchSubscriptionPage(cfg.URL, cfg.Fixture, client)
+	if err != nil {
+		return err
+	}
+	records, err := parseCoresHubPricingCatalog(raw)
+	if err != nil {
+		return err
+	}
+	records = dedupeOfficialPricingRecords(records)
+	if cfg.DryRun {
+		_, err = fmt.Fprintf(out, "source=coreshub-pricing-import models=%d operator=%s dry_run=true\n", len(records), records[0].OperatorName)
+		return err
+	}
+	if db == nil {
+		return fmt.Errorf("db is required when dry-run=false")
+	}
+	if err := upsertOfficialPricingRecords(db, records, "coreshub-pricing-import"); err != nil {
+		return err
+	}
+
+	var tableRows int
+	if err := db.QueryRow(`SELECT COUNT(*) FROM region_pricing`).Scan(&tableRows); err != nil {
+		return fmt.Errorf("count region_pricing: %w", err)
+	}
+	_, err = fmt.Fprintf(out, "source=coreshub-pricing-import models=%d operator=%s table_rows=%d dry_run=false\n", len(records), records[0].OperatorName, tableRows)
+	return err
+}